diff --git a/sleekxmpp/basexmpp.py b/sleekxmpp/basexmpp.py
index 3cf949a..a490510 100644
--- a/sleekxmpp/basexmpp.py
+++ b/sleekxmpp/basexmpp.py
@@ -106,6 +106,7 @@ class BaseXMPP(XMLStream):
 
         self.default_ns = default_ns
         self.stream_ns = 'http://etherx.jabber.org/streams'
+        self.namespace_map[self.stream_ns] = 'stream'
 
         self.boundjid = JID("")
 
@@ -119,6 +120,8 @@ class BaseXMPP(XMLStream):
 
         self.sentpresence = False
 
+        self.stanza = sleekxmpp.stanza
+
         self.register_handler(
             Callback('IM',
                      MatchXPath('{%s}message/{%s}body' % (self.default_ns,
diff --git a/sleekxmpp/xmlstream/stanzabase.py b/sleekxmpp/xmlstream/stanzabase.py
index 3937a7a..83d8699 100644
--- a/sleekxmpp/xmlstream/stanzabase.py
+++ b/sleekxmpp/xmlstream/stanzabase.py
@@ -1007,7 +1007,9 @@ class ElementBase(object):
         """
         Return a string serialization of the underlying XML object.
         """
-        return tostring(self.xml, xmlns='', stanza_ns=self.namespace)
+        return tostring(self.xml, xmlns='',
+                        stanza_ns=self.namespace,
+                        top_level=True)
 
     def __repr__(self):
         """
@@ -1217,4 +1219,5 @@ class StanzaBase(ElementBase):
         """Serialize the stanza's XML to a string."""
         return tostring(self.xml, xmlns='',
                         stanza_ns=self.namespace,
-                        stream=self.stream)
+                        stream=self.stream,
+                        top_level = True)
diff --git a/sleekxmpp/xmlstream/tostring/tostring.py b/sleekxmpp/xmlstream/tostring/tostring.py
index 38b08d8..a6bb6eb 100644
--- a/sleekxmpp/xmlstream/tostring/tostring.py
+++ b/sleekxmpp/xmlstream/tostring/tostring.py
@@ -7,7 +7,8 @@
 """
 
 
-def tostring(xml=None, xmlns='', stanza_ns='', stream=None, outbuffer=''):
+def tostring(xml=None, xmlns='', stanza_ns='', stream=None,
+             outbuffer='', top_level=False):
     """
     Serialize an XML object to a Unicode string.
 
@@ -26,6 +27,8 @@ def tostring(xml=None, xmlns='', stanza_ns='', stream=None, outbuffer=''):
         stream    -- The XML stream that generated the XML object.
         outbuffer -- Optional buffer for storing serializations during
                      recursive calls.
+        top_level -- Indicates that the element is the outermost
+                     element.
     """
     # Add previous results to the start of the output.
     output = [outbuffer]
@@ -39,14 +42,21 @@ def tostring(xml=None, xmlns='', stanza_ns='', stream=None, outbuffer=''):
     else:
         tag_xmlns = ''
 
+    default_ns = ''
+    stream_ns = ''
+    if stream:
+        default_ns = stream.default_ns
+        stream_ns = stream.stream_ns
+
     # Output the tag name and derived namespace of the element.
     namespace = ''
-    if tag_xmlns not in ['', xmlns, stanza_ns]:
+    if top_level and tag_xmlns not in ['', default_ns, stream_ns] or \
+            tag_xmlns not in ['', xmlns, stanza_ns, stream_ns]:
         namespace = ' xmlns="%s"' % tag_xmlns
-        if stream and tag_xmlns in stream.namespace_map:
-            mapped_namespace = stream.namespace_map[tag_xmlns]
-            if mapped_namespace:
-                tag_name = "%s:%s" % (mapped_namespace, tag_name)
+    if stream and tag_xmlns in stream.namespace_map:
+        mapped_namespace = stream.namespace_map[tag_xmlns]
+        if mapped_namespace:
+            tag_name = "%s:%s" % (mapped_namespace, tag_name)
     output.append("<%s" % tag_name)
     output.append(namespace)
 
diff --git a/sleekxmpp/xmlstream/tostring/tostring26.py b/sleekxmpp/xmlstream/tostring/tostring26.py
index 1150178..3d1ca3d 100644
--- a/sleekxmpp/xmlstream/tostring/tostring26.py
+++ b/sleekxmpp/xmlstream/tostring/tostring26.py
@@ -10,7 +10,8 @@ from __future__ import unicode_literals
 import types
 
 
-def tostring(xml=None, xmlns='', stanza_ns='', stream=None, outbuffer=''):
+def tostring(xml=None, xmlns='', stanza_ns='', stream=None,
+             outbuffer='', top_level=False):
     """
     Serialize an XML object to a Unicode string.
 
@@ -29,6 +30,8 @@ def tostring(xml=None, xmlns='', stanza_ns='', stream=None, outbuffer=''):
         stream    -- The XML stream that generated the XML object.
         outbuffer -- Optional buffer for storing serializations during
                      recursive calls.
+        top_level -- Indicates that the element is the outermost
+                     element.
     """
     # Add previous results to the start of the output.
     output = [outbuffer]
@@ -42,14 +45,21 @@ def tostring(xml=None, xmlns='', stanza_ns='', stream=None, outbuffer=''):
     else:
         tag_xmlns = u''
 
+    default_ns = ''
+    stream_ns = ''
+    if stream:
+        default_ns = stream.default_ns
+        stream_ns = stream.stream_ns
+
     # Output the tag name and derived namespace of the element.
     namespace = u''
-    if tag_xmlns not in ['', xmlns, stanza_ns]:
+    if top_level and tag_xmlns not in ['', default_ns, stream_ns] or \
+            tag_xmlns not in ['', xmlns, stanza_ns, stream_ns]:
         namespace = u' xmlns="%s"' % tag_xmlns
-        if stream and tag_xmlns in stream.namespace_map:
-            mapped_namespace = stream.namespace_map[tag_xmlns]
-            if mapped_namespace:
-                tag_name = u"%s:%s" % (mapped_namespace, tag_name)
+    if stream and tag_xmlns in stream.namespace_map:
+        mapped_namespace = stream.namespace_map[tag_xmlns]
+        if mapped_namespace:
+            tag_name = u"%s:%s" % (mapped_namespace, tag_name)
     output.append(u"<%s" % tag_name)
     output.append(namespace)
 
diff --git a/tests/test_tostring.py b/tests/test_tostring.py
index 638e613..e456d28 100644
--- a/tests/test_tostring.py
+++ b/tests/test_tostring.py
@@ -102,11 +102,13 @@ class TestToString(SleekTest):
         """
         Test that stanza objects are serialized properly.
         """
+        self.stream_start()
+
         utf8_message = '\xe0\xb2\xa0_\xe0\xb2\xa0'
         if not hasattr(utf8_message, 'decode'):
             # Python 3
             utf8_message = bytes(utf8_message, encoding='utf-8')
-        msg = Message()
+        msg = self.Message()
         msg['body'] = utf8_message.decode('utf-8')
         expected = '<message><body>\xe0\xb2\xa0_\xe0\xb2\xa0</body></message>'
         result = msg.__str__()