Hi I can't say I've ever seen this before - it may well have to do with the fact that JBoss Cache is not an XA resource and hence doesn't go through the steps to register itself as an XA resource with an XA compliant TM. This should not impact any functionality though, except XA recovery, but in a cache's case this would typically be to flush the cache. Anyway, I have created a JIRA issue to investigate the WARN message: JBCACHE-1254 Could you please confirm - on the JIRA - the versions of JBoss Cache and JBoss TS, as well as the environment (i.e., within an app server, etc)? Cheers, Manik View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4117053#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...