Index: domish.py
===================================================================
--- domish.py	(revision 26062)
+++ domish.py	(working copy)
@@ -15,6 +15,12 @@
 
 from zope.interface import implements, Interface, Attribute
 
+try:
+    import cserialize
+    USE_CSERIALIZE = True
+except ImportError:
+    USE_CSERIALIZE = False
+
 def _splitPrefix(name):
     """ Internal method for splitting a prefixed Element name into its
         respective parts """
@@ -45,7 +51,7 @@
 
     def getPrefix(self, uri):
         if not self.prefixes.has_key(uri):
-            self.prefixes[uri] = "xn%d" % (self.prefixCounter)
+            self.prefixes[uri] = "ns%d" % (self.prefixCounter)
             self.prefixCounter = self.prefixCounter + 1
         return self.prefixes[uri]
 
@@ -539,9 +545,16 @@
     def toXml(self, prefixes=None, closeElement=1, defaultUri='',
                     prefixesInScope=None):
         """ Serialize this Element and all children to a string. """
-        s = SerializerClass(prefixes=prefixes, prefixesInScope=prefixesInScope)
-        s.serialize(self, closeElement=closeElement, defaultUri=defaultUri)
-        return s.getValue()
+        if USE_CSERIALIZE:
+            return cserialize.serialize(self, prefixes=prefixes,
+                                        prefixesInScope=prefixesInScope,
+                                        closeElement=closeElement,
+                                        defaultUri=defaultUri)
+        else:
+            s = SerializerClass(prefixes=prefixes,
+                                prefixesInScope=prefixesInScope)
+            s.serialize(self, closeElement=closeElement, defaultUri=defaultUri)
+            return s.getValue()
 
     def firstChildElement(self):
         for c in self.children: