It is probably best to go down the first suggestion. One issue is that we are currently closing down sessions that are deemed unreliable. One example of this is an issue which is evident with JBoss Messaging, ironically using XASessions, where the XAResource appears to get into an inconsistent state and is, after that point, unusable. We have no real choice but to attempt to close down the session and create a new one, currently from the same connection. In addition we need to track the connection/session association as any errors returned through the listener will force a closure of the connection and sessions, with sessions returning to the pool later being discarded rather than reused, and we will need to handle this without affecting the other sessions/connections in this pool. It would also be a good idea to consider separating the XA/non-XA connections resources in case a provider enforces different limits per type, such as in the error you are trying to reproduce. Kev View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4230169#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...