diff --git a/sleekxmpp/plugins/xep_0004/stanza/field.py b/sleekxmpp/plugins/xep_0004/stanza/field.py
index 8131233..6814e15 100644
--- a/sleekxmpp/plugins/xep_0004/stanza/field.py
+++ b/sleekxmpp/plugins/xep_0004/stanza/field.py
@@ -79,19 +79,21 @@ class FormField(ElementBase):
         reqXML = self.xml.find('{%s}required' % self.namespace)
         return reqXML is not None
 
-    def get_value(self):
+    def get_value(self, convert=True):
         valsXML = self.xml.findall('{%s}value' % self.namespace)
         if len(valsXML) == 0:
             return None
         elif self._type == 'boolean':
-            return valsXML[0].text in self.true_values
+            if convert:
+                return valsXML[0].text in self.true_values
+            return valsXML[0].text
         elif self._type in self.multi_value_types or len(valsXML) > 1:
             values = []
             for valXML in valsXML:
                 if valXML.text is None:
                     valXML.text = ''
                 values.append(valXML.text)
-            if self._type == 'text-multi':
+            if self._type == 'text-multi' and condense:
                 values = "\n".join(values)
             return values
         else:
diff --git a/sleekxmpp/plugins/xep_0030/disco.py b/sleekxmpp/plugins/xep_0030/disco.py
index 53086d4..10f9ef4 100644
--- a/sleekxmpp/plugins/xep_0030/disco.py
+++ b/sleekxmpp/plugins/xep_0030/disco.py
@@ -10,7 +10,7 @@ import logging
 
 import sleekxmpp
 from sleekxmpp import Iq
-from sleekxmpp.exceptions import XMPPError
+from sleekxmpp.exceptions import XMPPError, IqError, IqTimeout
 from sleekxmpp.plugins.base import base_plugin
 from sleekxmpp.xmlstream.handler import Callback
 from sleekxmpp.xmlstream.matcher import StanzaPath
@@ -108,11 +108,16 @@ class xep_0030(base_plugin):
 
         self.static = StaticDisco(self.xmpp)
 
-        self._disco_ops = ['get_info', 'set_identities', 'set_features',
-                           'get_items', 'set_items', 'del_items',
-                           'add_identity', 'del_identity', 'add_feature',
-                           'del_feature', 'add_item', 'del_item',
-                           'del_identities', 'del_features']
+        self.use_cache = self.config.get('use_cache', True)
+        self.wrap_results = self.config.get('wrap_results', False)
+
+        self._disco_ops = [
+                'get_info', 'set_info', 'set_identities', 'set_features',
+                'get_items', 'set_items', 'del_items', 'add_identity',
+                'del_identity', 'add_feature', 'del_feature', 'add_item',
+                'del_item', 'del_identities', 'del_features', 'cache_info',
+                'get_cached_info', 'supports', 'has_identity']
+        
         self.default_handlers = {}
         self._handlers = {}
         for op in self._disco_ops:
@@ -237,7 +242,78 @@ class xep_0030(base_plugin):
             self.del_node_handler(op, jid, node)
             self.set_node_handler(op, jid, node, self.default_handlers[op])
 
-    def get_info(self, jid=None, node=None, local=False, **kwargs):
+    def supports(self, jid=None, node=None, feature=None, local=False, 
+                       cached=True, ifrom=None):
+        """
+        Check if a JID supports a given feature.
+
+        Return values:
+            True  -- The feature is supported
+            False -- The feature is not listed as supported
+            None  -- Nothing could be found due to a timeout
+
+        Arguments:
+            jid      -- Request info from this JID.
+            node     -- The particular node to query.
+            feature  -- The name of the feature to check.
+            local    -- If true, then the query is for a JID/node
+                        combination handled by this Sleek instance and
+                        no stanzas need to be sent.
+                        Otherwise, a disco stanza must be sent to the
+                        remove JID to retrieve the info.
+            cached   -- If true, then look for the disco info data from
+                        the local cache system. If no results are found,
+                        send the query as usual. The self.use_cache
+                        setting must be set to true for this option to
+                        be useful. If set to false, then the cache will
+                        be skipped, even if a result has already been
+                        cached. Defaults to false.
+            ifrom    -- Specifiy the sender's JID.
+        """
+        data = {'feature': feature,
+                'local': local,
+                'cached': cached}
+        return self._run_node_handler('supports', jid, node, ifrom, data)
+ 
+    def has_identity(self, jid=None, node=None, category=None, itype=None,
+                     lang=None, local=False, cached=True, ifrom=None):
+        """
+        Check if a JID provides a given identity.
+
+        Return values:
+            True  -- The identity is provided 
+            False -- The identity is not listed
+            None  -- Nothing could be found due to a timeout
+
+        Arguments:
+            jid      -- Request info from this JID.
+            node     -- The particular node to query.
+            category -- The category of the identity to check.
+            itype    -- The type of the identity to check.
+            lang     -- The language of the identity to check.
+            local    -- If true, then the query is for a JID/node
+                        combination handled by this Sleek instance and
+                        no stanzas need to be sent.
+                        Otherwise, a disco stanza must be sent to the
+                        remove JID to retrieve the info.
+            cached   -- If true, then look for the disco info data from
+                        the local cache system. If no results are found,
+                        send the query as usual. The self.use_cache
+                        setting must be set to true for this option to
+                        be useful. If set to false, then the cache will
+                        be skipped, even if a result has already been
+                        cached. Defaults to false.
+            ifrom    -- Specifiy the sender's JID.
+        """
+        data = {'category': category,
+                'itype': itype,
+                'lang': lang,
+                'local': local,
+                'cached': cached}
+        return self._run_node_handler('has_identity', jid, node, ifrom, data)
+            
+    def get_info(self, jid=None, node=None, local=False, 
+                       cached=None, **kwargs):
         """
         Retrieve the disco#info results from a given JID/node combination.
 
@@ -257,6 +333,13 @@ class xep_0030(base_plugin):
                         no stanzas need to be sent.
                         Otherwise, a disco stanza must be sent to the
                         remove JID to retrieve the info.
+            cached   -- If true, then look for the disco info data from
+                        the local cache system. If no results are found,
+                        send the query as usual. The self.use_cache
+                        setting must be set to true for this option to
+                        be useful. If set to false, then the cache will
+                        be skipped, even if a result has already been
+                        cached. Defaults to false.
             ifrom    -- Specifiy the sender's JID.
             block    -- If true, block and wait for the stanzas' reply.
             timeout  -- The time in seconds to block while waiting for
@@ -266,12 +349,31 @@ class xep_0030(base_plugin):
                         received instead of blocking and waiting for
                         the reply.
         """
-        if local or jid is None:
+        if jid is not None and not isinstance(jid, JID):
+            jid = JID(jid)
+            if self.xmpp.is_component:
+                if jid.domain == self.xmpp.boundjid.domain:
+                    local = True
+            else:
+                if str(jid) == str(self.xmpp.boundjid):
+                    local = True
+
+        if local or jid in (None, ''):
             log.debug("Looking up local disco#info data " + \
                       "for %s, node %s.", jid, node)
-            info = self._run_node_handler('get_info', jid, node, kwargs)
-            return self._fix_default_info(info)
+            info = self._run_node_handler('get_info', 
+                    jid, node, kwargs.get('ifrom', None), kwargs)
+            info = self._fix_default_info(info)
+            return self._wrap(kwargs.get('ifrom', None), jid, info)
 
+        if cached:
+            log.debug("Looking up cached disco#info data " + \
+                      "for %s, node %s.", jid, node)
+            info = self._run_node_handler('get_cached_info', 
+                    jid, node, kwargs.get('ifrom', None), kwargs)
+            if info is not None:
+                return self._wrap(kwargs.get('ifrom', None), jid, info)
+            
         iq = self.xmpp.Iq()
         # Check dfrom parameter for backwards compatibility
         iq['from'] = kwargs.get('ifrom', kwargs.get('dfrom', ''))
@@ -282,6 +384,15 @@ class xep_0030(base_plugin):
                        block=kwargs.get('block', True),
                        callback=kwargs.get('callback', None))
 
+    def set_info(self, jid=None, node=None, info=None):
+        """
+        Set the disco#info data for a JID/node based on an existing
+        disco#info stanza.
+        """
+        if isinstance(info, Iq):
+            info = info['disco_info']
+        self._run_node_handler('set_info', jid, node, None, info)
+
     def get_items(self, jid=None, node=None, local=False, **kwargs):
         """
         Retrieve the disco#items results from a given JID/node combination.
@@ -314,7 +425,9 @@ class xep_0030(base_plugin):
                         Otherwise the parameter is ignored.
         """
         if local or jid is None:
-            return self._run_node_handler('get_items', jid, node, kwargs)
+            items = self._run_node_handler('get_items', 
+                    jid, node, kwargs.get('ifrom', None), kwargs)
+            return self._wrap(kwargs.get('ifrom', None), jid, items)
 
         iq = self.xmpp.Iq()
         # Check dfrom parameter for backwards compatibility
@@ -341,7 +454,7 @@ class xep_0030(base_plugin):
             node  -- Optional node to modify.
             items -- A series of items in tuple format.
         """
-        self._run_node_handler('set_items', jid, node, kwargs)
+        self._run_node_handler('set_items', jid, node, None, kwargs)
 
     def del_items(self, jid=None, node=None, **kwargs):
         """
@@ -351,7 +464,7 @@ class xep_0030(base_plugin):
             jid  -- The JID to modify.
             node -- Optional node to modify.
         """
-        self._run_node_handler('del_items', jid, node, kwargs)
+        self._run_node_handler('del_items', jid, node, None, kwargs)
 
     def add_item(self, jid='', name='', node=None, subnode='', ijid=None):
         """
@@ -372,7 +485,7 @@ class xep_0030(base_plugin):
         kwargs = {'ijid': jid,
                   'name': name,
                   'inode': subnode}
-        self._run_node_handler('add_item', ijid, node, kwargs)
+        self._run_node_handler('add_item', ijid, node, None, kwargs)
 
     def del_item(self, jid=None, node=None, **kwargs):
         """
@@ -384,7 +497,7 @@ class xep_0030(base_plugin):
             ijid  -- The item's JID.
             inode -- The item's node.
         """
-        self._run_node_handler('del_item', jid, node, kwargs)
+        self._run_node_handler('del_item', jid, node, None, kwargs)
 
     def add_identity(self, category='', itype='', name='',
                      node=None, jid=None, lang=None):
@@ -411,7 +524,7 @@ class xep_0030(base_plugin):
                   'itype': itype,
                   'name': name,
                   'lang': lang}
-        self._run_node_handler('add_identity', jid, node, kwargs)
+        self._run_node_handler('add_identity', jid, node, None, kwargs)
 
     def add_feature(self, feature, node=None, jid=None):
         """
@@ -423,7 +536,7 @@ class xep_0030(base_plugin):
             jid     -- The JID to modify.
         """
         kwargs = {'feature': feature}
-        self._run_node_handler('add_feature', jid, node, kwargs)
+        self._run_node_handler('add_feature', jid, node, None, kwargs)
 
     def del_identity(self, jid=None, node=None, **kwargs):
         """
@@ -437,7 +550,7 @@ class xep_0030(base_plugin):
             name     -- Optional, human readable name for the identity.
             lang     -- Optional, the identity's xml:lang value.
         """
-        self._run_node_handler('del_identity', jid, node, kwargs)
+        self._run_node_handler('del_identity', jid, node, None, kwargs)
 
     def del_feature(self, jid=None, node=None, **kwargs):
         """
@@ -448,7 +561,7 @@ class xep_0030(base_plugin):
             node    -- The node to modify.
             feature -- The feature's namespace.
         """
-        self._run_node_handler('del_feature', jid, node, kwargs)
+        self._run_node_handler('del_feature', jid, node, None, kwargs)
 
     def set_identities(self, jid=None, node=None, **kwargs):
         """
@@ -463,7 +576,7 @@ class xep_0030(base_plugin):
             identities -- A set of identities in tuple form.
             lang       -- Optional, xml:lang value.
         """
-        self._run_node_handler('set_identities', jid, node, kwargs)
+        self._run_node_handler('set_identities', jid, node, None, kwargs)
 
     def del_identities(self, jid=None, node=None, **kwargs):
         """
@@ -478,7 +591,7 @@ class xep_0030(base_plugin):
             lang -- Optional. If given, only remove identities
                     using this xml:lang value.
         """
-        self._run_node_handler('del_identities', jid, node, kwargs)
+        self._run_node_handler('del_identities', jid, node, None, kwargs)
 
     def set_features(self, jid=None, node=None, **kwargs):
         """
@@ -490,7 +603,7 @@ class xep_0030(base_plugin):
             node     -- The node to modify.
             features -- The new set of supported features.
         """
-        self._run_node_handler('set_features', jid, node, kwargs)
+        self._run_node_handler('set_features', jid, node, None, kwargs)
 
     def del_features(self, jid=None, node=None, **kwargs):
         """
@@ -500,9 +613,9 @@ class xep_0030(base_plugin):
             jid  -- The JID to modify.
             node -- The node to modify.
         """
-        self._run_node_handler('del_features', jid, node, kwargs)
+        self._run_node_handler('del_features', jid, node, None, kwargs)
 
-    def _run_node_handler(self, htype, jid, node, data={}):
+    def _run_node_handler(self, htype, jid, node=None, ifrom=None, data={}):
         """
         Execute the most specific node handler for the given
         JID/node combination.
@@ -513,7 +626,7 @@ class xep_0030(base_plugin):
             node  -- The node requested.
             data  -- Optional, custom data to pass to the handler.
         """
-        if jid is None:
+        if jid in (None, ''):
             if self.xmpp.is_component:
                 jid = self.xmpp.boundjid.full
             else:
@@ -521,14 +634,28 @@ class xep_0030(base_plugin):
         if node is None:
             node = ''
 
-        if self._handlers[htype]['node'].get((jid, node), False):
-            return self._handlers[htype]['node'][(jid, node)](jid, node, data)
-        elif self._handlers[htype]['jid'].get(jid, False):
-            return self._handlers[htype]['jid'][jid](jid, node, data)
-        elif self._handlers[htype]['global']:
-            return self._handlers[htype]['global'](jid, node, data)
-        else:
-            return None
+        try:
+            args = (jid, node, ifrom, data)
+            if self._handlers[htype]['node'].get((jid, node), False):
+                return self._handlers[htype]['node'][(jid, node)](*args)
+            elif self._handlers[htype]['jid'].get(jid, False):
+                return self._handlers[htype]['jid'][jid](*args)
+            elif self._handlers[htype]['global']:
+                return self._handlers[htype]['global'](*args)
+            else:
+                return None
+        except TypeError:
+            # To preserve backward compatibility, drop the ifrom parameter
+            # for existing handlers that don't understand it.
+            args = (jid, node, data)
+            if self._handlers[htype]['node'].get((jid, node), False):
+                return self._handlers[htype]['node'][(jid, node)](*args)
+            elif self._handlers[htype]['jid'].get(jid, False):
+                return self._handlers[htype]['jid'][jid](*args)
+            elif self._handlers[htype]['global']:
+                return self._handlers[htype]['global'](*args)
+            else:
+                return None
 
     def _handle_disco_info(self, iq):
         """
@@ -550,6 +677,7 @@ class xep_0030(base_plugin):
             info = self._run_node_handler('get_info',
                                           jid,
                                           iq['disco_info']['node'],
+                                          iq['from'],
                                           iq)
             if isinstance(info, Iq):
                 info.send()
@@ -560,8 +688,20 @@ class xep_0030(base_plugin):
                     iq.set_payload(info.xml)
                 iq.send()
         elif iq['type'] == 'result':
-            log.debug("Received disco info result from" + \
-                      "%s to %s.", iq['from'], iq['to'])
+            log.debug("Received disco info result from " + \
+                      "<%s> to <%s>.", iq['from'], iq['to'])
+            if self.use_cache:
+                log.debug("Caching disco info result from " \
+                      "<%s> to <%s>.", iq['from'], iq['to'])
+                if self.xmpp.is_component:
+                    ito = iq['to'].full
+                else:
+                    ito = None
+                self._run_node_handler('cache_info',
+                                       iq['from'].full,
+                                       iq['disco_info']['node'],
+                                       ito,
+                                       iq)
             self.xmpp.event('disco_info', iq)
 
     def _handle_disco_items(self, iq):
@@ -583,6 +723,7 @@ class xep_0030(base_plugin):
             items = self._run_node_handler('get_items',
                                           jid,
                                           iq['disco_items']['node'],
+                                          iq['from'].full,
                                           iq)
             if isinstance(items, Iq):
                 items.send()
@@ -592,7 +733,7 @@ class xep_0030(base_plugin):
                     iq.set_payload(items.xml)
                 iq.send()
         elif iq['type'] == 'result':
-            log.debug("Received disco items result from" + \
+            log.debug("Received disco items result from " + \
                       "%s to %s.", iq['from'], iq['to'])
             self.xmpp.event('disco_items', iq)
 
@@ -607,21 +748,46 @@ class xep_0030(base_plugin):
         Arguments:
             info -- The disco#info quest (not the full Iq stanza) to modify.
         """
+        result = info
+        if isinstance(info, Iq):
+            info = iq['disco_info']
         if not info['node']:
             if not info['identities']:
                 if self.xmpp.is_component:
-                    log.debug("No identity found for this entity." + \
+                    log.debug("No identity found for this entity. " + \
                               "Using default component identity.")
                     info.add_identity('component', 'generic')
                 else:
-                    log.debug("No identity found for this entity." + \
+                    log.debug("No identity found for this entity. " + \
                               "Using default client identity.")
                     info.add_identity('client', 'bot')
             if not info['features']:
-                log.debug("No features found for this entity." + \
+                log.debug("No features found for this entity. " + \
                           "Using default disco#info feature.")
                 info.add_feature(info.namespace)
-        return info
+        return result
+
+    def _wrap(self, ito, ifrom, payload, force=False):
+        """
+        Ensure that results are wrapped in an Iq stanza
+        if self.wrap_results has been set to True.
+
+        Arguments:
+            ito     -- The JID to use as the 'to' value
+            ifrom   -- The JID to use as the 'from' value
+            payload -- The disco data to wrap
+            force   -- Force wrapping, regardless of self.wrap_results
+        """
+        if (force or self.wrap_results) and not isinstance(payload, Iq):
+            iq = self.xmpp.Iq()
+            # Since we're simulating a result, we have to treat
+            # the 'from' and 'to' values opposite the normal way.
+            iq['to'] = self.xmpp.boundjid if ito is None else ito
+            iq['from'] = self.xmpp.boundjid if ifrom is None else ifrom
+            iq['type'] = 'result'
+            iq.append(payload)
+            return iq
+        return payload
 
 
 # Retain some backwards compatibility
diff --git a/sleekxmpp/plugins/xep_0030/stanza/info.py b/sleekxmpp/plugins/xep_0030/stanza/info.py
index 6764acb..25d1d07 100644
--- a/sleekxmpp/plugins/xep_0030/stanza/info.py
+++ b/sleekxmpp/plugins/xep_0030/stanza/info.py
@@ -146,7 +146,7 @@ class DiscoInfo(ElementBase):
                     return True
         return False
 
-    def get_identities(self, lang=None):
+    def get_identities(self, lang=None, dedupe=True):
         """
         Return a set of all identities in tuple form as so:
             (category, type, lang, name)
@@ -155,17 +155,25 @@ class DiscoInfo(ElementBase):
         that language.
 
         Arguments:
-            lang -- Optional, standard xml:lang value.
+            lang   -- Optional, standard xml:lang value.
+            dedupe -- If True, de-duplicate identities, otherwise
+                      return a list of all identities.
         """
-        identities = set()
+        if dedupe:
+            identities = set()
+        else:
+            identities = []
         for id_xml in self.findall('{%s}identity' % self.namespace):
             xml_lang = id_xml.attrib.get('{%s}lang' % self.xml_ns, None)
             if lang is None or xml_lang == lang:
-                identities.add((
-                    id_xml.attrib['category'],
-                    id_xml.attrib['type'],
-                    id_xml.attrib.get('{%s}lang' % self.xml_ns, None),
-                    id_xml.attrib.get('name', None)))
+                id = (id_xml.attrib['category'],
+                      id_xml.attrib['type'],
+                      id_xml.attrib.get('{%s}lang' % self.xml_ns, None),
+                      id_xml.attrib.get('name', None))
+                if dedupe:
+                    identities.add(id)
+                else:
+                    identities.append(id)
         return identities
 
     def set_identities(self, identities, lang=None):
@@ -237,11 +245,17 @@ class DiscoInfo(ElementBase):
                     return True
         return False
 
-    def get_features(self):
+    def get_features(self, dedupe=True):
         """Return the set of all supported features."""
-        features = set()
+        if dedupe:
+            features = set()
+        else:
+            features = []
         for feature_xml in self.findall('{%s}feature' % self.namespace):
-            features.add(feature_xml.attrib['var'])
+            if dedupe:
+                features.add(feature_xml.attrib['var'])
+            else:
+                features.append(feature_xml.attrib['var'])
         return features
 
     def set_features(self, features):
diff --git a/sleekxmpp/plugins/xep_0030/static.py b/sleekxmpp/plugins/xep_0030/static.py
index 7e7f035..0b196b4 100644
--- a/sleekxmpp/plugins/xep_0030/static.py
+++ b/sleekxmpp/plugins/xep_0030/static.py
@@ -7,6 +7,7 @@
 """
 
 import logging
+import threading
 
 import sleekxmpp
 from sleekxmpp import Iq
@@ -50,8 +51,10 @@ class StaticDisco(object):
         """
         self.nodes = {}
         self.xmpp = xmpp
+        self.disco = xmpp['xep_0030']
+        self.lock = threading.RLock()
 
-    def add_node(self, jid=None, node=None):
+    def add_node(self, jid=None, node=None, ifrom=None):
         """
         Create a new set of stanzas for the provided
         JID and node combination.
@@ -60,83 +63,219 @@ class StaticDisco(object):
             jid  -- The JID that will own the new stanzas.
             node -- The node that will own the new stanzas.
         """
-        if jid is None:
-            jid = self.xmpp.boundjid.full
-        if node is None:
-            node = ''
-        if (jid, node) not in self.nodes:
-            self.nodes[(jid, node)] = {'info': DiscoInfo(),
-                                       'items': DiscoItems()}
-            self.nodes[(jid, node)]['info']['node'] = node
-            self.nodes[(jid, node)]['items']['node'] = node
+        with self.lock:
+            if jid is None:
+                jid = self.xmpp.boundjid.full
+            if node is None:
+                node = ''
+            if ifrom is None:
+                ifrom = ''
+            if isinstance(ifrom, JID):
+                ifrom = ifrom.full
+            if (jid, node, ifrom) not in self.nodes:
+                self.nodes[(jid, node, ifrom)] = {'info': DiscoInfo(),
+                                           'items': DiscoItems()}
+                self.nodes[(jid, node, ifrom)]['info']['node'] = node
+                self.nodes[(jid, node, ifrom)]['items']['node'] = node
+
+    def get_node(self, jid=None, node=None, ifrom=None):
+        with self.lock:
+            if jid is None:
+                jid = self.xmpp.boundjid.full
+            if node is None:
+                node = ''
+            if ifrom is None:
+                ifrom = ''
+            if isinstance(ifrom, JID):
+                ifrom = ifrom.full
+            if (jid, node, ifrom) not in self.nodes:
+                self.add_node(jid, node, ifrom)
+            return self.nodes[(jid, node, ifrom)]
+
+    def node_exists(self, jid=None, node=None, ifrom=None):
+        with self.lock:
+            if jid is None:
+                jid = self.xmpp.boundjid.full
+            if node is None:
+                node = ''
+            if ifrom is None:
+                ifrom = ''
+            if isinstance(ifrom, JID):
+                ifrom = ifrom.full
+            if (jid, node, ifrom) not in self.nodes:
+                return False
+            return True 
 
     # =================================================================
     # Node Handlers
     #
-    # Each handler accepts three arguments: jid, node, and data.
-    # The jid and node parameters together determine the set of
-    # info and items stanzas that will be retrieved or added.
-    # The data parameter is a dictionary with additional paramters
-    # that will be passed to other calls.
+    # Each handler accepts four arguments: jid, node, ifrom, and data.
+    # The jid and node parameters together determine the set of info
+    # and items stanzas that will be retrieved or added. Additionally,
+    # the ifrom value allows for cached results when results vary based
+    # on the requester's JID. The data parameter is a dictionary with
+    # additional parameters that will be passed to other calls.
+    #
+    # This implementation does not allow different responses based on
+    # the requester's JID, except for cached results. To do that, 
+    # register a custom node handler.
 
-    def get_info(self, jid, node, data):
+    def supports(self, jid, node, ifrom, data):
+        """
+        Check if a JID supports a given feature.
+
+        The data parameter may provide:
+            feature  -- The feature to check for support.
+            local    -- If true, then the query is for a JID/node
+                        combination handled by this Sleek instance and
+                        no stanzas need to be sent.
+                        Otherwise, a disco stanza must be sent to the
+                        remove JID to retrieve the info.
+            cached   -- If true, then look for the disco info data from
+                        the local cache system. If no results are found,
+                        send the query as usual. The self.use_cache
+                        setting must be set to true for this option to
+                        be useful. If set to false, then the cache will
+                        be skipped, even if a result has already been
+                        cached. Defaults to false.
+        """
+        feature = data.get('feature', None)
+
+        data = {'local': data.get('local', False),
+                'cached': data.get('cached', True)}
+
+        if not feature:
+            return False
+
+        try:
+            info = self.disco.get_info(jid=jid, node=node, 
+                                       ifrom=ifrom, **data)
+            info = self.disco._wrap(ifrom, jid, info, True)
+            features = info['disco_info']['features']
+            return feature in features
+        except IqError:
+            return False
+        except IqTimeout:
+            return None
+
+    def has_identity(self, jid, node, ifrom, data):
+        """
+        Check if a JID has a given identity.
+
+        The data parameter may provide:
+            category -- The category of the identity to check.
+            itype    -- The type of the identity to check.
+            lang     -- The language of the identity to check.
+            local    -- If true, then the query is for a JID/node
+                        combination handled by this Sleek instance and
+                        no stanzas need to be sent.
+                        Otherwise, a disco stanza must be sent to the
+                        remove JID to retrieve the info.
+            cached   -- If true, then look for the disco info data from
+                        the local cache system. If no results are found,
+                        send the query as usual. The self.use_cache
+                        setting must be set to true for this option to
+                        be useful. If set to false, then the cache will
+                        be skipped, even if a result has already been
+                        cached. Defaults to false.
+        """
+        identity = (data.get('category', None), 
+                    data.get('itype', None),
+                    data.get('lang', None))
+
+        data = {'local': data.get('local', False),
+                'cached': data.get('cached', True)}
+
+        if node in (None, ''):
+            info = self.caps.get_caps(jid)
+            if info and identity in info['identities']:
+                return True
+
+        try:
+            info = self.disco.get_info(jid=jid, node=node, 
+                                       ifrom=ifrom, **data)
+            info = self.disco._wrap(ifrom, jid, info, True)
+            trunc = lambda i: (i[0], i[1], i[2])
+            return identity in map(trunc, info['disco_info']['identities'])
+        except IqError:
+            return False
+        except IqTimeout:
+            return None
+
+
+    def get_info(self, jid, node, ifrom, data):
         """
         Return the stored info data for the requested JID/node combination.
 
         The data parameter is not used.
         """
-        if (jid, node) not in self.nodes:
-            if not node:
-                return DiscoInfo()
+        with self.lock:
+            if not self.node_exists(jid, node):
+                if not node:
+                    return DiscoInfo()
+                else:
+                    raise XMPPError(condition='item-not-found')
             else:
-                raise XMPPError(condition='item-not-found')
-        else:
-            return self.nodes[(jid, node)]['info']
+                return self.get_node(jid, node)['info']
 
-    def del_info(self, jid, node, data):
+    def set_info(self, jid, node, ifrom, data):
+        """
+        Set the entire info stanza for a JID/node at once.
+
+        The data parameter is a disco#info substanza.
+        """
+        with self.lock:
+            self.add_node(jid, node)
+            self.get_node(jid, node)['info'] = data
+
+    def del_info(self, jid, node, ifrom, data):
         """
         Reset the info stanza for a given JID/node combination.
 
         The data parameter is not used.
         """
-        if (jid, node) in self.nodes:
-            self.nodes[(jid, node)]['info'] = DiscoInfo()
+        with self.lock:
+            if self.node_exists(jid, node):
+                self.get_node(jid, node)['info'] = DiscoInfo()
 
-    def get_items(self, jid, node, data):
+    def get_items(self, jid, node, ifrom, data):
         """
         Return the stored items data for the requested JID/node combination.
 
         The data parameter is not used.
         """
-        if (jid, node) not in self.nodes:
-            if not node:
-                return DiscoInfo()
+        with self.lock:
+            if not self.node_exists(jid, node):
+                if not node:
+                    return DiscoInfo()
+                else:
+                    raise XMPPError(condition='item-not-found')
             else:
-                raise XMPPError(condition='item-not-found')
-        else:
-            return self.nodes[(jid, node)]['items']
+                return self.get_node(jid, node)['items']
 
-    def set_items(self, jid, node, data):
+    def set_items(self, jid, node, ifrom, data):
         """
         Replace the stored items data for a JID/node combination.
 
-        The data parameter may provided:
+        The data parameter may provide:
             items -- A set of items in tuple format.
         """
-        items = data.get('items', set())
-        self.add_node(jid, node)
-        self.nodes[(jid, node)]['items']['items'] = items
+        with self.lock:
+            items = data.get('items', set())
+            self.add_node(jid, node)
+            self.get_node(jid, node)['items']['items'] = items
 
-    def del_items(self, jid, node, data):
+    def del_items(self, jid, node, ifrom, data):
         """
         Reset the items stanza for a given JID/node combination.
 
         The data parameter is not used.
         """
-        if (jid, node) in self.nodes:
-            self.nodes[(jid, node)]['items'] = DiscoItems()
+        with self.lock:
+            if self.node_exists(jid, node):
+                self.get_node(jid, node)['items'] = DiscoItems()
 
-    def add_identity(self, jid, node, data):
+    def add_identity(self, jid, node, ifrom, data):
         """
         Add a new identity to te JID/node combination.
 
@@ -146,14 +285,15 @@ class StaticDisco(object):
             name     -- Optional human readable name for this identity.
             lang     -- Optional standard xml:lang value.
         """
-        self.add_node(jid, node)
-        self.nodes[(jid, node)]['info'].add_identity(
-                data.get('category', ''),
-                data.get('itype', ''),
-                data.get('name', None),
-                data.get('lang', None))
+        with self.lock:
+            self.add_node(jid, node)
+            self.get_node(jid, node)['info'].add_identity(
+                    data.get('category', ''),
+                    data.get('itype', ''),
+                    data.get('name', None),
+                    data.get('lang', None))
 
-    def set_identities(self, jid, node, data):
+    def set_identities(self, jid, node, ifrom, data):
         """
         Add or replace all identities for a JID/node combination.
 
@@ -161,11 +301,12 @@ class StaticDisco(object):
             identities -- A list of identities in tuple form:
                             (category, type, name, lang)
         """
-        identities = data.get('identities', set())
-        self.add_node(jid, node)
-        self.nodes[(jid, node)]['info']['identities'] = identities
+        with self.lock:
+            identities = data.get('identities', set())
+            self.add_node(jid, node)
+            self.get_node(jid, node)['info']['identities'] = identities
 
-    def del_identity(self, jid, node, data):
+    def del_identity(self, jid, node, ifrom, data):
         """
         Remove an identity from a JID/node combination.
 
@@ -175,67 +316,70 @@ class StaticDisco(object):
             name     -- Optional human readable name for this identity.
             lang     -- Optional, standard xml:lang value.
         """
-        if (jid, node) not in self.nodes:
-            return
-        self.nodes[(jid, node)]['info'].del_identity(
-                data.get('category', ''),
-                data.get('itype', ''),
-                data.get('name', None),
-                data.get('lang', None))
+        with self.lock:
+            if self.node_exists(jid, node):
+                self.get_node(jid, node)['info'].del_identity(
+                        data.get('category', ''),
+                        data.get('itype', ''),
+                        data.get('name', None),
+                        data.get('lang', None))
 
-    def del_identities(self, jid, node, data):
+    def del_identities(self, jid, node, ifrom, data):
         """
         Remove all identities from a JID/node combination.
 
         The data parameter is not used.
         """
-        if (jid, node) not in self.nodes:
-            return
-        del self.nodes[(jid, node)]['info']['identities']
+        with self.lock:
+            if self.node_exists(jid, node):
+                del self.get_node(jid, node)['info']['identities']
 
-    def add_feature(self, jid, node, data):
+    def add_feature(self, jid, node, ifrom, data):
         """
         Add a feature to a JID/node combination.
 
         The data parameter should include:
             feature -- The namespace of the supported feature.
         """
-        self.add_node(jid, node)
-        self.nodes[(jid, node)]['info'].add_feature(data.get('feature', ''))
+        with self.lock:
+            self.add_node(jid, node)
+            self.get_node(jid, node)['info'].add_feature(data.get('feature', ''))
 
-    def set_features(self, jid, node, data):
+    def set_features(self, jid, node, ifrom, data):
         """
         Add or replace all features for a JID/node combination.
 
         The data parameter should include:
             features -- The new set of supported features.
         """
-        features = data.get('features', set())
-        self.add_node(jid, node)
-        self.nodes[(jid, node)]['info']['features'] = features
+        with self.lock:
+            features = data.get('features', set())
+            self.add_node(jid, node)
+            self.get_node(jid, node)['info']['features'] = features
 
-    def del_feature(self, jid, node, data):
+    def del_feature(self, jid, node, ifrom, data):
         """
         Remove a feature from a JID/node combination.
 
         The data parameter should include:
             feature -- The namespace of the removed feature.
         """
-        if (jid, node) not in self.nodes:
-            return
-        self.nodes[(jid, node)]['info'].del_feature(data.get('feature', ''))
+        with self.lock:
+            if self.node_exists(jid, node):
+                self.get_node(jid, node)['info'].del_feature(data.get('feature', ''))
 
-    def del_features(self, jid, node, data):
+    def del_features(self, jid, node, ifrom, data):
         """
         Remove all features from a JID/node combination.
 
         The data parameter is not used.
         """
-        if (jid, node) not in self.nodes:
-            return
-        del self.nodes[(jid, node)]['info']['features']
+        with self.lock:
+            if not self.node_exists(jid, node):
+                return
+            del self.get_node(jid, node)['info']['features']
 
-    def add_item(self, jid, node, data):
+    def add_item(self, jid, node, ifrom, data):
         """
         Add an item to a JID/node combination.
 
@@ -245,13 +389,14 @@ class StaticDisco(object):
                      non-addressable items.
             name  -- Optional human readable name for the item.
         """
-        self.add_node(jid, node)
-        self.nodes[(jid, node)]['items'].add_item(
-                data.get('ijid', ''),
-                node=data.get('inode', ''),
-                name=data.get('name', ''))
+        with self.lock:
+            self.add_node(jid, node)
+            self.get_node(jid, node)['items'].add_item(
+                    data.get('ijid', ''),
+                    node=data.get('inode', ''),
+                    name=data.get('name', ''))
 
-    def del_item(self, jid, node, data):
+    def del_item(self, jid, node, ifrom, data):
         """
         Remove an item from a JID/node combination.
 
@@ -259,7 +404,38 @@ class StaticDisco(object):
             ijid  -- JID of the item to remove.
             inode -- Optional extra identifying information.
         """
-        if (jid, node) in self.nodes:
-            self.nodes[(jid, node)]['items'].del_item(
-                    data.get('ijid', ''),
-                    node=data.get('inode', None))
+        with self.lock:
+            if self.node_exists(jid, node):
+                self.get_node(jid, node)['items'].del_item(
+                        data.get('ijid', ''),
+                        node=data.get('inode', None))
+
+    def cache_info(self, jid, node, ifrom, data):
+        """
+        Cache disco information for an external JID.
+
+        The data parameter is the Iq result stanza
+        containing the disco info to cache, or
+        the disco#info substanza itself.
+        """
+        with self.lock:
+            if isinstance(data, Iq):
+                data = data['disco_info']
+
+            self.add_node(jid, node, ifrom)
+            self.get_node(jid, node, ifrom)['info'] = data
+
+    def get_cached_info(self, jid, node, ifrom, data):
+        """
+        Retrieve cached disco info data.
+
+        The data parameter is not used.
+        """
+        with self.lock:
+            if isinstance(jid, JID):
+                jid = jid.full
+
+            if not self.node_exists(jid, node, ifrom):
+                return None
+            else:
+                return self.get_node(jid, node, ifrom)['info']
diff --git a/sleekxmpp/plugins/xep_0115/__init__.py b/sleekxmpp/plugins/xep_0115/__init__.py
new file mode 100644
index 0000000..f4892f8
--- /dev/null
+++ b/sleekxmpp/plugins/xep_0115/__init__.py
@@ -0,0 +1,11 @@
+"""
+    SleekXMPP: The Sleek XMPP Library
+    Copyright (C) 2011 Nathanael C. Fritz, Lance J.T. Stout
+    This file is part of SleekXMPP.
+
+    See the file LICENSE for copying permission.
+"""
+
+from sleekxmpp.plugins.xep_0115.stanza import Capabilities
+from sleekxmpp.plugins.xep_0115.static import StaticCaps
+from sleekxmpp.plugins.xep_0115.caps import xep_0115
diff --git a/sleekxmpp/plugins/xep_0115/caps.py b/sleekxmpp/plugins/xep_0115/caps.py
new file mode 100644
index 0000000..d3e62ab
--- /dev/null
+++ b/sleekxmpp/plugins/xep_0115/caps.py
@@ -0,0 +1,290 @@
+"""
+    SleekXMPP: The Sleek XMPP Library
+    Copyright (C) 2011 Nathanael C. Fritz, Lance J.T. Stout
+    This file is part of SleekXMPP.
+
+    See the file LICENSE for copying permission.
+"""
+
+import logging
+import hashlib
+import base64
+
+import sleekxmpp
+from sleekxmpp.stanza import StreamFeatures, Presence, Iq
+from sleekxmpp.xmlstream import register_stanza_plugin, JID
+from sleekxmpp.xmlstream.handler import Callback
+from sleekxmpp.xmlstream.matcher import StanzaPath
+from sleekxmpp.exceptions import XMPPError, IqError, IqTimeout
+from sleekxmpp.plugins.base import base_plugin
+from sleekxmpp.plugins.xep_0115 import stanza, StaticCaps
+
+
+log = logging.getLogger(__name__)
+
+
+class xep_0115(base_plugin):
+
+    """
+    XEP-0115: Entity Capabalities
+    """
+
+    def plugin_init(self):
+        self.xep = '0115'
+        self.description = 'Entity Capabilities'
+        self.stanza = stanza
+
+        self.hashes = {'sha-1': hashlib.sha1, 
+                       'md5': hashlib.md5}
+
+        self.hash = self.config.get('hash', 'sha-1')
+        self.caps_node = self.config.get('caps_node', None)
+        self.broadcast = self.config.get('broadcast', True)
+
+        if self.caps_node is None:
+            ver = sleekxmpp.__version__
+            self.caps_node = 'http://sleekxmpp.com/ver/%s' % ver
+
+        register_stanza_plugin(Presence, stanza.Capabilities)
+        register_stanza_plugin(StreamFeatures, stanza.Capabilities)
+
+        self._disco_ops = ['cache_caps',
+                           'get_caps',
+                           'assign_verstring',
+                           'get_verstring',
+                           'supports',
+                           'has_identity']
+
+        self.xmpp.register_handler(
+                Callback('Entity Capabilites',
+                         StanzaPath('presence/caps'),
+                         self._handle_caps))
+
+        self.xmpp.add_filter('out', self._filter_add_caps)
+
+        self.xmpp.add_event_handler('entity_caps', self._process_caps,
+                                    threaded=True)
+
+        self.xmpp.register_feature('caps',
+                self._handle_caps_feature,
+                restart=False,
+                order=10010)
+
+    def post_init(self):
+        base_plugin.post_init(self)
+        self.xmpp['xep_0030'].add_feature(stanza.Capabilities.namespace)
+
+        disco = self.xmpp['xep_0030']
+        self.static = StaticCaps(self.xmpp, disco.static)
+
+        for op in self._disco_ops:
+            disco._add_disco_op(op, getattr(self.static, op))
+
+        self._run_node_handler = disco._run_node_handler
+
+        disco.cache_caps = self.cache_caps
+        disco.update_caps = self.update_caps
+        disco.assign_verstring = self.assign_verstring
+        disco.get_verstring = self.get_verstring
+
+    def _filter_add_caps(self, stanza):
+        if isinstance(stanza, Presence) and self.broadcast:
+            ver = self.get_verstring(stanza['from'])
+            if ver:
+                stanza['caps']['node'] = self.caps_node
+                stanza['caps']['hash'] = self.hash
+                stanza['caps']['ver'] = ver
+        return stanza
+
+    def _handle_caps(self, presence):
+        if not self.xmpp.is_component:
+            if presence['from'] == self.xmpp.boundjid:
+                return
+        self.xmpp.event('entity_caps', presence)
+
+    def _handle_caps_feature(self, features):
+        # We already have a method to process presence with
+        # caps, so wrap things up and use that.
+        p = Presence()
+        p['from'] = self.xmpp.boundjid.domain
+        p.append(features['caps'])
+        self.xmpp.features.add('caps')
+
+        self.xmpp.event('entity_caps', p)
+
+    def _process_caps(self, pres):
+        if not pres['caps']['hash']:
+            log.debug("Received unsupported legacy caps.")
+            self.xmpp.event('entity_caps_legacy', pres)
+            return
+
+        existing_verstring = self.get_verstring(pres['from'].full)
+        if str(existing_verstring) == str(pres['caps']['ver']):
+            return
+     
+        if pres['caps']['hash'] not in self.hashes:
+            try:
+                log.debug("Unknown caps hash: %s", pres['caps']['hash'])
+                self.xmpp['xep_003'].get_info(jid=pres['from'].full)
+                return
+            except XMPPError:
+                return
+   
+        log.debug("New caps verification string: %s", pres['caps']['ver'])
+        try:
+            caps = self.xmpp['xep_0030'].get_info(
+                    jid=pres['from'].full,
+                    node='%s#%s' % (pres['caps']['node'],
+                                    pres['caps']['ver']))
+                    
+            if self._validate_caps(caps['disco_info'], 
+                                   pres['caps']['hash'],
+                                   pres['caps']['ver']):
+                self.assign_verstring(pres['from'], pres['caps']['ver'])
+        except XMPPError:
+            log.debug("Could not retrieve disco#info results for caps")
+
+    def _validate_caps(self, caps, hash, check_verstring):
+        # Check Identities
+        full_ids = caps.get_identities(dedupe=False)
+        deduped_ids = caps.get_identities()
+        if len(full_ids) != len(deduped_ids):
+            log.debug("Duplicate disco identities found, invalid for caps")
+            return False
+
+        # Check Features
+
+        full_features = caps.get_features(dedupe=False)
+        deduped_features = caps.get_features()
+        if len(full_features) != len(deduped_features):
+            log.debug("Duplicate disco features found, invalid for caps")
+            return False
+
+        # Check Forms
+        form_types = []
+        deduped_form_types = set()
+        for stanza in caps['substanzas']:
+            if isinstance(stanza, self.xmpp['xep_0004'].stanza.Form):
+                if 'FORM_TYPE' in stanza['fields']:
+                    f_type = tuple(stanza['fields']['FORM_TYPE']['value'])
+                    form_types.append(f_type)
+                    deduped_form_types.add(f_type)
+                    if len(form_types) != len(deduped_form_types):
+                        log.debug("Duplicated FORM_TYPE values, invalid for caps")
+                        return False
+
+                    if len(f_type) > 1:
+                        deduped_type = set(f_type)
+                        if len(f_type) != len(deduped_type):
+                            log.debug("Extra FORM_TYPE data, invalid for caps")
+                            return False
+
+                    if stanza['fields']['FORM_TYPE']['type'] != 'hidden':
+                        log.debug("Field FORM_TYPE type not 'hidden', ignoring form for caps")
+                        caps.xml.remove(stanza.xml)
+                else:
+                    log.debug("No FORM_TYPE found, ignoring form for caps")
+                    caps.xml.remove(stanza.xml)
+
+        verstring = self.generate_verstring(caps, hash)
+        if verstring != check_verstring:
+            log.debug("Verification strings do not match: %s, %s" % (
+                verstring, check_verstring))
+            return False
+
+        self.cache_caps(verstring, caps)
+        return True
+
+    def generate_verstring(self, info, hash):
+        hash = self.hashes.get(hash, None)
+        if hash is None:
+            return None
+
+        S = ''
+
+        # Convert None to '' in the identities
+        def clean_identity(id):
+            return map(lambda i: i or '', id)
+        identities = map(clean_identity, info['identities'])
+
+        identities = sorted(('/'.join(i) for i in identities))
+        features = sorted(info['features'])
+ 
+        S += '<'.join(identities) + '<'
+        S += '<'.join(features) + '<'
+
+        form_types = {}
+
+        for stanza in info['substanzas']:
+            if isinstance(stanza, self.xmpp['xep_0004'].stanza.Form):
+                if 'FORM_TYPE' in stanza['fields']:
+                    f_type = stanza['values']['FORM_TYPE']
+                    if len(f_type):
+                        f_type = f_type[0]
+                    if f_type not in form_types:
+                        form_types[f_type] = []
+                    form_types[f_type].append(stanza)
+
+        sorted_forms = sorted(form_types.keys())
+        for f_type in sorted_forms:
+            for form in form_types[f_type]:
+                S += '%s<' % f_type
+                fields = sorted(form['fields'].keys())
+                fields.remove('FORM_TYPE')
+                for field in fields:
+                    S += '%s<' % field
+                    vals = form['fields'][field].get_value(convert=False)
+                    if vals is None:
+                        S += '<'
+                    else:
+                        if not isinstance(vals, list):
+                            vals = [vals]
+                        S += '<'.join(sorted(vals)) + '<'
+
+        binary = hash(S.encode('utf8')).digest()
+        return base64.b64encode(binary).decode('utf-8')
+
+    def update_caps(self, jid=None, node=None):
+        try:
+            info = self.xmpp['xep_0030'].get_info(jid, node, local=True)
+            if isinstance(info, Iq):
+                info = info['disco_info']
+            ver = self.generate_verstring(info, self.hash)
+            self.xmpp['xep_0030'].set_info(
+                    jid=jid, 
+                    node='%s#%s' % (self.caps_node, ver),
+                    info=info)
+            self.cache_caps(ver, info)
+            self.assign_verstring(jid, ver)
+        except XMPPError:
+            return
+
+    def get_verstring(self, jid=None):
+        if jid in ('', None):
+            jid = self.xmpp.boundjid.full
+        if isinstance(jid, JID):
+            jid = jid.full
+        return self._run_node_handler('get_verstring', jid)
+
+    def assign_verstring(self, jid=None, verstring=None):
+        if jid in (None, ''):
+            jid = self.xmpp.boundjid.full
+        if isinstance(jid, JID):
+            jid = jid.full
+        return self._run_node_handler('assign_verstring', jid, 
+                                      data={'verstring': verstring})
+
+    def cache_caps(self, verstring=None, info=None):
+        data = {'verstring': verstring, 'info': info}
+        return self._run_node_handler('cache_caps', None, None, data=data)
+
+    def get_caps(self, jid=None, verstring=None):
+        if verstring is None:
+            if jid is not None:
+                verstring = self.get_verstring(jid)
+            else:
+                return None
+        if isinstance(jid, JID):
+            jid = jid.full
+        data = {'verstring': verstring}
+        return self._run_node_handler('get_caps', jid, None, None, data)
diff --git a/sleekxmpp/plugins/xep_0115/stanza.py b/sleekxmpp/plugins/xep_0115/stanza.py
new file mode 100644
index 0000000..af02949
--- /dev/null
+++ b/sleekxmpp/plugins/xep_0115/stanza.py
@@ -0,0 +1,19 @@
+"""
+    SleekXMPP: The Sleek XMPP Library
+    Copyright (C) 2011 Nathanael C. Fritz, Lance J.T. Stout
+    This file is part of SleekXMPP.
+
+    See the file LICENSE for copying permission.
+"""
+
+from __future__ import unicode_literals
+
+from sleekxmpp.xmlstream import ElementBase, ET
+
+
+class Capabilities(ElementBase):
+
+    namespace = 'http://jabber.org/protocol/caps'
+    name = 'c'
+    plugin_attrib = 'caps'
+    interfaces = set(('hash', 'node', 'ver', 'ext'))
diff --git a/sleekxmpp/plugins/xep_0115/static.py b/sleekxmpp/plugins/xep_0115/static.py
new file mode 100644
index 0000000..204181d
--- /dev/null
+++ b/sleekxmpp/plugins/xep_0115/static.py
@@ -0,0 +1,147 @@
+"""
+    SleekXMPP: The Sleek XMPP Library
+    Copyright (C) 2011 Nathanael C. Fritz, Lance J.T. Stout
+    This file is part of SleekXMPP.
+
+    See the file LICENSE for copying permission.
+"""
+
+import logging
+
+import sleekxmpp
+from sleekxmpp.xmlstream import JID
+from sleekxmpp.plugins.xep_0030 import StaticDisco
+
+
+log = logging.getLogger(__name__)
+
+
+class StaticCaps(object):
+
+    """
+    Extend the default StaticDisco implementation to provide
+    support for extended identity information.
+    """
+
+    def __init__(self, xmpp, static):
+        """
+        Augment the default XEP-0030 static handler object.
+
+        Arguments:
+            static -- The default static XEP-0030 handler object.
+        """
+        self.xmpp = xmpp
+        self.disco = self.xmpp['xep_0030']
+        self.caps = self.xmpp['xep_0115']
+        self.static = static
+        self.ver_cache = {}
+        self.jid_vers = {}
+
+    def supports(self, jid, node, ifrom, data):
+        """
+        Check if a JID supports a given feature.
+
+        The data parameter may provide:
+            feature  -- The feature to check for support.
+            local    -- If true, then the query is for a JID/node
+                        combination handled by this Sleek instance and
+                        no stanzas need to be sent.
+                        Otherwise, a disco stanza must be sent to the
+                        remove JID to retrieve the info.
+            cached   -- If true, then look for the disco info data from
+                        the local cache system. If no results are found,
+                        send the query as usual. The self.use_cache
+                        setting must be set to true for this option to
+                        be useful. If set to false, then the cache will
+                        be skipped, even if a result has already been
+                        cached. Defaults to false.
+        """
+        feature = data.get('feature', None)
+
+        data = {'local': data.get('local', False),
+                'cached': data.get('cached', True)}
+
+        if not feature:
+            return False
+
+        if node in (None, ''):
+            info = self.caps.get_caps(jid)
+            if info and feature in info['features']:
+                return True
+
+        try:
+            info = self.disco.get_info(jid=jid, node=node, 
+                                       ifrom=ifrom, **data)
+            info = self.disco._wrap(ifrom, jid, info, True)
+            return feature in info['disco_info']['features']
+        except IqError:
+            return False
+        except IqTimeout:
+            return None
+
+    def has_identity(self, jid, node, ifrom, data):
+        """
+        Check if a JID has a given identity.
+
+        The data parameter may provide:
+            category -- The category of the identity to check.
+            itype    -- The type of the identity to check.
+            lang     -- The language of the identity to check.
+            local    -- If true, then the query is for a JID/node
+                        combination handled by this Sleek instance and
+                        no stanzas need to be sent.
+                        Otherwise, a disco stanza must be sent to the
+                        remove JID to retrieve the info.
+            cached   -- If true, then look for the disco info data from
+                        the local cache system. If no results are found,
+                        send the query as usual. The self.use_cache
+                        setting must be set to true for this option to
+                        be useful. If set to false, then the cache will
+                        be skipped, even if a result has already been
+                        cached. Defaults to false.
+        """
+        identity = (data.get('category', None), 
+                    data.get('itype', None),
+                    data.get('lang', None))
+
+        data = {'local': data.get('local', False),
+                'cached': data.get('cached', True)}
+
+        trunc = lambda i: (i[0], i[1], i[2])
+
+        if node in (None, ''):
+            info = self.caps.get_caps(jid)
+            if info and identity in map(trunc, info['identities']):
+                return True
+
+        try:
+            info = self.disco.get_info(jid=jid, node=node, 
+                                       ifrom=ifrom, **data)
+            info = self.disco._wrap(ifrom, jid, info, True)
+            return identity in map(trunc, info['disco_info']['identities'])
+        except IqError:
+            return False
+        except IqTimeout:
+            return None
+
+    def cache_caps(self, jid, node, ifrom, data):
+        with self.static.lock:
+            verstring = data.get('verstring', None)
+            info = data.get('info', None)
+            if not verstring or not info:
+                return
+            self.ver_cache[verstring] = info
+
+    def assign_verstring(self, jid, node, ifrom, data):
+        with self.static.lock:
+            if isinstance(jid, JID):
+                jid = jid.full
+            self.jid_vers[jid] = data.get('verstring', None)
+
+    def get_verstring(self, jid, node, ifrom, data):
+        with self.static.lock:
+            return self.jid_vers.get(jid, None)
+
+    def get_caps(self, jid, node, ifrom, data):
+        with self.static.lock:
+            return self.ver_cache.get(data.get('verstring', None), None)
diff --git a/sleekxmpp/plugins/xep_0128/extended_disco.py b/sleekxmpp/plugins/xep_0128/extended_disco.py
index 63b3cfe..5bb7832 100644
--- a/sleekxmpp/plugins/xep_0128/extended_disco.py
+++ b/sleekxmpp/plugins/xep_0128/extended_disco.py
@@ -76,7 +76,7 @@ class xep_0128(base_plugin):
                     as extended information, replacing any
                     existing extensions.
         """
-        self.disco._run_node_handler('set_extended_info', jid, node, kwargs)
+        self.disco._run_node_handler('set_extended_info', jid, node, None, kwargs)
 
     def add_extended_info(self, jid=None, node=None, **kwargs):
         """
@@ -88,7 +88,7 @@ class xep_0128(base_plugin):
             data -- Either a form, or a list of forms to add
                     as extended information.
         """
-        self.disco._run_node_handler('add_extended_info', jid, node, kwargs)
+        self.disco._run_node_handler('add_extended_info', jid, node, None, kwargs)
 
     def del_extended_info(self, jid=None, node=None, **kwargs):
         """
@@ -98,4 +98,4 @@ class xep_0128(base_plugin):
             jid  -- The JID to modify.
             node -- The node to modify.
         """
-        self.disco._run_node_handler('del_extended_info', jid, node, kwargs)
+        self.disco._run_node_handler('del_extended_info', jid, node, None, kwargs)
diff --git a/sleekxmpp/plugins/xep_0128/static.py b/sleekxmpp/plugins/xep_0128/static.py
index 493d937..427011c 100644
--- a/sleekxmpp/plugins/xep_0128/static.py
+++ b/sleekxmpp/plugins/xep_0128/static.py
@@ -31,42 +31,43 @@ class StaticExtendedDisco(object):
         """
         self.static = static
 
-    def set_extended_info(self, jid, node, data):
+    def set_extended_info(self, jid, node, ifrom, data):
         """
         Replace the extended identity data for a JID/node combination.
 
         The data parameter may provide:
             data -- Either a single data form, or a list of data forms.
         """
-        self.del_extended_info(jid, node, data)
-        self.add_extended_info(jid, node, data)
+        with self.static.lock:
+            self.del_extended_info(jid, node, ifrom, data)
+            self.add_extended_info(jid, node, ifrom, data)
 
-    def add_extended_info(self, jid, node, data):
+    def add_extended_info(self, jid, node, ifrom, data):
         """
         Add additional extended identity data for a JID/node combination.
 
         The data parameter may provide:
             data -- Either a single data form, or a list of data forms.
         """
-        self.static.add_node(jid, node)
+        with self.static.lock:
+            self.static.add_node(jid, node)
 
-        forms = data.get('data', [])
-        if not isinstance(forms, list):
-            forms = [forms]
+            forms = data.get('data', [])
+            if not isinstance(forms, list):
+                forms = [forms]
 
-        for form in forms:
-            self.static.nodes[(jid, node)]['info'].append(form)
+            info = self.static.get_node(jid, node)['info']
+            for form in forms:
+                info.append(form)
 
-    def del_extended_info(self, jid, node, data):
+    def del_extended_info(self, jid, node, ifrom, data):
         """
         Replace the extended identity data for a JID/node combination.
 
         The data parameter is not used.
         """
-        if (jid, node) not in self.static.nodes:
-            return
-
-        info = self.static.nodes[(jid, node)]['info']
-
-        for form in info['substanza']:
-            info.xml.remove(form.xml)
+        with self.static.lock:
+            if self.static.node_exists(jid, node):
+                info = self.static.get_node(jid, node)['info']
+                for form in info['substanza']:
+                    info.xml.remove(form.xml)
diff --git a/sleekxmpp/xmlstream/stanzabase.py b/sleekxmpp/xmlstream/stanzabase.py
index 721181a..d140970 100644
--- a/sleekxmpp/xmlstream/stanzabase.py
+++ b/sleekxmpp/xmlstream/stanzabase.py
@@ -345,7 +345,8 @@ class ElementBase(object):
         """
         if attrib not in self.plugins:
             plugin_class = self.plugin_attrib_map[attrib]
-            plugin = plugin_class(parent=self)
+            existing_xml = self.xml.find(plugin_class.tag_name())
+            plugin = plugin_class(parent=self, xml=existing_xml)
             self.plugins[attrib] = plugin
             if plugin_class in self.plugin_iterables:
                 self.iterables.append(plugin)
@@ -1251,7 +1252,7 @@ class StanzaBase(ElementBase):
                          stanza sent immediately. Useful for stream
                          initialization. Defaults to ``False``.
         """
-        self.stream.send_raw(self.__str__(), now=now)
+        self.stream.send(self, now=now)
 
     def __copy__(self):
         """Return a copy of the stanza object that does not share the
diff --git a/sleekxmpp/xmlstream/xmlstream.py b/sleekxmpp/xmlstream/xmlstream.py
index fb9f91b..d502992 100644
--- a/sleekxmpp/xmlstream/xmlstream.py
+++ b/sleekxmpp/xmlstream/xmlstream.py
@@ -35,7 +35,7 @@ except ImportError:
 import sleekxmpp
 from sleekxmpp.thirdparty.statemachine import StateMachine
 from sleekxmpp.xmlstream import Scheduler, tostring
-from sleekxmpp.xmlstream.stanzabase import StanzaBase, ET
+from sleekxmpp.xmlstream.stanzabase import StanzaBase, ET, ElementBase
 from sleekxmpp.xmlstream.handler import Waiter, XMLCallback
 from sleekxmpp.xmlstream.matcher import MatchXMLMask
 
@@ -268,6 +268,7 @@ class XMLStream(object):
         self.__handlers = []
         self.__event_handlers = {}
         self.__event_handlers_lock = threading.Lock()
+        self.__filters = {'in': [], 'out': []}
 
         self._id = 0
         self._id_lock = threading.Lock()
@@ -743,6 +744,28 @@ class XMLStream(object):
         """
         del self.__root_stanza[stanza_class]
 
+    def add_filter(self, mode, handler, order=None):
+        """Add a filter for incoming or outgoing stanzas.
+
+        These filters are applied before incoming stanzas are
+        passed to any handlers, and before outgoing stanzas
+        are put in the send queue.
+
+        Each filter must accept a single stanza, and return
+        either a stanza or ``None``. If the filter returns
+        ``None``, then the stanza will be dropped from being
+        processed for events or from being sent.
+
+        :param mode: One of ``'in'`` or ``'out'``.
+        :param handler: The filter function.
+        :param int order: The position to insert the filter in
+                          the list of active filters.
+        """
+        if order:
+            self.__filters[mode].insert(order, handler)
+        else:
+            self.__filters[mode].append(handler)
+
     def add_handler(self, mask, pointer, name=None, disposable=False,
                     threaded=False, filter=False, instream=False):
         """A shortcut method for registering a handler using XML masks.
@@ -994,6 +1017,14 @@ class XMLStream(object):
             timeout = self.response_timeout
         if hasattr(mask, 'xml'):
             mask = mask.xml
+
+        if isinstance(data, ElementBase):
+            for filter in self.__filters['out']:
+                if data is not None:
+                    data = filter(data)
+            if data is None:
+                return
+
         data = str(data)
         if mask is not None:
             log.warning("Use of send mask waiters is deprecated.")
@@ -1246,8 +1277,6 @@ class XMLStream(object):
         :param xml: The :class:`~sleekxmpp.xmlstream.stanzabase.ElementBase`
                     stanza to analyze.
         """
-        log.debug("RECV: %s", tostring(xml, xmlns=self.default_ns,
-                                            stream=self))
         # Apply any preprocessing filters.
         xml = self.incoming_filter(xml)
 
@@ -1255,6 +1284,15 @@ class XMLStream(object):
         # stanza type applies, a generic StanzaBase stanza will be used.
         stanza = self._build_stanza(xml)
 
+        for filter in self.__filters['in']:
+            if stanza is not None:
+                stanza = filter(stanza)
+        if stanza is None:
+            return
+
+        log.debug("RECV: %s", tostring(xml, xmlns=self.default_ns,
+                                            stream=self))
+
         # Match the stanza against registered handlers. Handlers marked
         # to run "in stream" will be executed immediately; the rest will
         # be queued.
diff --git a/tests/test_stream_filters.py b/tests/test_stream_filters.py
new file mode 100644
index 0000000..ef4d5dc
--- /dev/null
+++ b/tests/test_stream_filters.py
@@ -0,0 +1,88 @@
+import time
+
+from sleekxmpp import Message
+from sleekxmpp.test import *
+from sleekxmpp.xmlstream.handler import *
+from sleekxmpp.xmlstream.matcher import *
+
+
+class TestFilters(SleekTest):
+
+    """
+    Test using incoming and outgoing filters.
+    """
+
+    def setUp(self):
+        self.stream_start()
+
+    def tearDown(self):
+        self.stream_close()
+
+    def testIncoming(self):
+
+        data = []
+
+        def in_filter(stanza):
+            if isinstance(stanza, Message):
+                if stanza['body'] == 'testing':
+                    stanza['subject'] = stanza['body'] + ' filter'
+                    print('>>> %s' % stanza['subject'])
+            return stanza
+
+        def on_message(msg):
+            print('<<< %s' % msg['subject'])
+            data.append(msg['subject'])
+
+        self.xmpp.add_filter('in', in_filter)
+        self.xmpp.add_event_handler('message', on_message)
+
+        self.recv("""
+          <message>
+            <body>no filter</body>
+          </message>
+        """)
+
+        self.recv("""
+          <message>
+            <body>testing</body>
+          </message>
+        """)
+
+        time.sleep(0.5)
+
+        self.assertEqual(data, ['', 'testing filter'],
+                'Incoming filter did not apply %s' % data)
+
+    def testOutgoing(self):
+
+        def out_filter(stanza):
+            if isinstance(stanza, Message):
+                if stanza['body'] == 'testing':
+                    stanza['body'] = 'changed!'
+            return stanza
+
+        self.xmpp.add_filter('out', out_filter)
+
+        m1 = self.Message()
+        m1['body'] = 'testing'
+        m1.send()
+
+        m2 = self.Message()
+        m2['body'] = 'blah'
+        m2.send()
+
+        self.send("""
+          <message>
+            <body>changed!</body>
+          </message>
+        """)
+
+        self.send("""
+          <message>
+            <body>blah</body>
+          </message>
+        """)
+
+
+ 
+suite = unittest.TestLoader().loadTestsFromTestCase(TestFilters)
diff --git a/tests/test_stream_xep_0030.py b/tests/test_stream_xep_0030.py
index 1666d3a..dd43778 100644
--- a/tests/test_stream_xep_0030.py
+++ b/tests/test_stream_xep_0030.py
@@ -122,7 +122,7 @@ class TestStreamDisco(SleekTest):
         self.stream_start(mode='client',
                           plugins=['xep_0030'])
 
-        def dynamic_jid(jid, node, iq):
+        def dynamic_jid(jid, node, ifrom, iq):
             result = self.xmpp['xep_0030'].stanza.DiscoInfo()
             result['node'] = node
             result.add_identity('client', 'console', name='Dynamic Info')
@@ -158,7 +158,7 @@ class TestStreamDisco(SleekTest):
                           jid='tester.localhost',
                           plugins=['xep_0030'])
 
-        def dynamic_global(jid, node, iq):
+        def dynamic_global(jid, node, ifrom, iq):
             result = self.xmpp['xep_0030'].stanza.DiscoInfo()
             result['node'] = node
             result.add_identity('component', 'generic', name='Dynamic Info')
@@ -194,7 +194,7 @@ class TestStreamDisco(SleekTest):
         self.stream_start(mode='client',
                           plugins=['xep_0030'])
 
-        def dynamic_jid(jid, node, iq):
+        def dynamic_jid(jid, node, ifrom, iq):
             result = self.xmpp['xep_0030'].stanza.DiscoInfo()
             result['node'] = node
             result.add_identity('client', 'console', name='Dynamic Info')
@@ -236,7 +236,7 @@ class TestStreamDisco(SleekTest):
                           jid='tester.localhost',
                           plugins=['xep_0030'])
 
-        def dynamic_global(jid, node, iq):
+        def dynamic_global(jid, node, ifrom, iq):
             result = self.xmpp['xep_0030'].stanza.DiscoInfo()
             result['node'] = node
             result.add_identity('component', 'generic', name='Dynamic Info')
@@ -325,7 +325,7 @@ class TestStreamDisco(SleekTest):
         self.stream_start(mode='client',
                           plugins=['xep_0030'])
 
-        def dynamic_jid(jid, node, iq):
+        def dynamic_jid(jid, node, ifrom, iq):
             result = self.xmpp['xep_0030'].stanza.DiscoItems()
             result['node'] = node
             result.add_item('tester@localhost', node='foo', name='JID')
@@ -359,7 +359,7 @@ class TestStreamDisco(SleekTest):
                           jid='tester.localhost',
                           plugins=['xep_0030'])
 
-        def dynamic_global(jid, node, iq):
+        def dynamic_global(jid, node, ifrom, iq):
             result = self.xmpp['xep_0030'].stanza.DiscoItems()
             result['node'] = node
             result.add_item('tester@localhost', node='foo', name='Global')
@@ -393,7 +393,7 @@ class TestStreamDisco(SleekTest):
         self.stream_start(mode='client',
                           plugins=['xep_0030'])
 
-        def dynamic_jid(jid, node, iq):
+        def dynamic_jid(jid, node, ifrom, iq):
             result = self.xmpp['xep_0030'].stanza.DiscoItems()
             result['node'] = node
             result.add_item('tester@localhost', node='foo', name='Global')
@@ -435,7 +435,7 @@ class TestStreamDisco(SleekTest):
                           jid='tester.localhost',
                           plugins=['xep_0030'])
 
-        def dynamic_global(jid, node, iq):
+        def dynamic_global(jid, node, ifrom, iq):
             result = self.xmpp['xep_0030'].stanza.DiscoItems()
             result['node'] = node
             result.add_item('tester.localhost', node='foo', name='Global')