I don't have experience with this. But here's what you could try - when after 450 messages, the MDB stops receiving, obtain the thread dumps and see if it provides any useful information. The thread dumps can be obtained as explained here http://www.jboss.org/community/docs/DOC-12300 Also, the http://localhost:8080/jmx-console has some MBeans (i am not at my system now so i can't tell you the exact names) which show you the status of the MDB (including the instance count and other stuff). See if that provides any clues. View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4212014#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...