The following XML snippet enables an application to receive XMPP messages. Insert it into the middle of the appengine-web.xml file in the /war/WEB-INF/ folder:
<!-- Enable all inbound services. -->
<inbound-services>
<service>xmpp_message</service>
<service>xmpp_presence</service>
<service>xmpp_subscribe</service>
<service>xmpp_error</service>
</inbound-services>