I did some tests and the following is going to be required in your *-ds.xml file. <isSameRM-override-value>false</isSameRM-override-value> IBM DB2 XA seems to suffer from the same Oracle issue wherein enlisting two managed connections within the same XA transaction will not work if the underlying resource manager is the same. Add this to your *-ds.xml file(s) and you should be all set. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=3991781#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...