Index: xmlrpcs.inc
===================================================================
RCS file: /cvs/drupal/drupal/includes/xmlrpcs.inc,v
retrieving revision 1.24
diff -u -r1.24 xmlrpcs.inc
--- xmlrpcs.inc	31 Dec 2007 08:54:36 -0000	1.24
+++ xmlrpcs.inc	10 Jan 2008 00:18:58 -0000
@@ -67,7 +67,7 @@
   xmlrpc_server_set($xmlrpc_server);
   $result = xmlrpc_server_call($xmlrpc_server, $xmlrpc_server->message->methodname, $xmlrpc_server->message->params);
 
-  if ($result->is_error) {
+  if (isset($result->is_error)) {
     xmlrpc_server_error($result);
   }
   // Encode the result