Thanks, Clebert. JGroups releases aren't interoperable (i.e. a server running 2.4.1 will have issues clustering with one on 2.4.1.SP1), so I don't know if you want to switch versions in an SP. That's somewhat a policy decision for the Messaging team. IMO the most significant thing in 2.4.1.SP1 for normal usage is the fix for http://jira.jboss.com/jira/browse/JGRP-422. We saw the error message reported on that JIRA pretty frequently during shutdown of an AS instance; I assume messaging users would as well. The effect of the problem is just the ERROR message; the shutdown happens correctly. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4029481#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...