All our 10 datasources are local-tx-datasource but it appears JBossTS (default transaction manager in 4.2.0) only allows 1 local-tx-datasource (not simple to find this out), you need to convert to xa-datasource. This should be in the release notes (I can find no reference). However, converting to xa-datasource on a Oracle database seems to be problematic. A conclusion I have reached after scanning these forums, scanning Google and trying it out. So I switched back to the 'deprecated' "fast in-memory transaction manager" which, in my view, should not be listed as 'deprecated' unless the default TM (JBossTS) supports multiple local-tx-datasource. Dave P.S. I think that this http://jira.jboss.com/jira/browse/JBAS-4425 is probably also going to screw up Oracle XA on 4.2 View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4048173#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...