--- /usr/lib/python2.3/xmlrpclib.py	2004-09-24 08:57:54.000000000 +0200
+++ ./xmlrpclib2.py	2004-11-20 15:50:16.000000000 +0100
@@ -611,7 +611,19 @@ class Marshaller:
         try:
             f = self.dispatch[type(value)]
         except KeyError:
-            raise TypeError, "cannot marshal %s objects" % type(value)
+            # check if this object can be marshalled as a structure
+            try:
+                value.__dict__
+            except:
+                raise TypeError, "cannot marshal %s objects" % type(value)
+            # check if this class is a sub-class of a basic type,
+            # because we don't know how to marshal these types
+            # (e.g. a string sub-class)
+            for type_ in type(value).__mro__:
+                if type_ in self.dispatch.keys():
+                    raise TypeError, "cannot marshal %s objects" % type(value)
+            f = self.dispatch[InstanceType]
+            f(self, value, write)
         else:
             f(self, value, write)
 
@@ -710,7 +722,7 @@ class Marshaller:
             # store instance attributes as a struct (really?)
             self.dump_struct(value.__dict__, write)
     dispatch[InstanceType] = dump_instance
-
+    
 ##
 # XML-RPC unmarshaller.
 #