Thanks Tim. I'm having trouble reproducing this consistently. I left a test run of our application when I left the office and it had been going for an hour with no problems. Will see what has happened in the morning. I'm trying to work out what we could be doing in our message listener that would upset messaging. We make sure that we catch all RuntimeExceptions and don't let them propogate up to JBoss, so I'm not sure what else it could be. I'll enhance the test harness to emulate all of the queues that we listen on. We have a manager class for each queue that creates a connection, the sessions and listeners so maybe it is the combination of multiple connections and sessions. We also register an exception listener on the connection to handle reconnects, but I don't think that is firing. Look forward to getting my hands on RC4. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=3962103#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...