Fixed NPE with IQ of type error.

git-svn-id: http://svn.igniterealtime.org/svn/repos/messenger/trunk@2930 b35dd754-fafc-0310-a699-88a17e54d16e

src/java/org/jivesoftware/messenger/muc/spi/MultiUserChatServerImpl.java

 /**
- * $RCSfile$
+ * $RCSfile: MultiUserChatServerImpl.java,v $
  * $Revision$
  * $Date$
  *
@@ -214,6 +214,10 @@ public class MultiUserChatServerImpl extends BasicModule implements MultiUserCha
     private boolean process(IQ iq) {
         Element childElement = iq.getChildElement();
         String namespace = null;
+        // Ignore IQs of type ERROR
+        if (IQ.Type.error == iq.getType()) {
+            return false;
+        }
         if (childElement != null) {
             namespace = childElement.getNamespaceURI();
         }