Hi, There is one subtility that can explain the issue : Trans1 ( persistance Unit 1) === (Required) ==> Trans2 (Persistance Unit 2) FAILS with could not enlist ... IMPORTANT : We use a new persistence unit in Trans2 Trans1 ( persistance Unit 1) === (RequiresNew) ==> Trans2 (Persistance Unit 2) WORKS ! The problem is perhaps related to the usage of 2 persistence unit when we joined the new transaction with Required I will attach the trace for the 2 scenarios regards, View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4030637#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...