Hi Tim, Thanks for your quick reply. The first problem, namely the failure to receive any JMS messages and the subsequent timeout exceptions on the server, does not occur when the explicit ip address is specified. In this case, the special client behaves just like any other "normal" client. I can't be sure whether the server lock-up is really related to this client. Probably yes, as up to now, we have observed the lock-up only when this peculiar client has attempted to connect (without providing the explicit ip address) several times. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4016435#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...