1. Even with using a thread pool, notifications for each call or transaction are performed by the same thread (see Notifier.invokeQueuedNotifications()) - a single Runnable is used to loop thru all registered listeners, for all registered notification events. So you will get pre and post events in order, and not concurrently. 2. Hmm, this could be a useful callback - txStarted, txCommitted, txROlledBack (with a Transaction object passed in? Is this useful?) Can't help but feel we're reinventing something here though. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4054725#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...