Hi Vicky/gsniderJBoss, I have read the link you sent already. The JBossTS 2.3 programming guide too. Went through the topic below that has a lot to do with my doubt: http://www.jboss.com/index.html?module=bb&op=viewtopic&t=95617&am... Here is a part of my JBoss log where I can see it referencing a XA resource: ---------------- [com.arjuna.ats.internal.jta.transaction.arjunacore.lastResource.multipleWarning] [com.arjuna.ats.internal.jta.transaction.arjunacore.lastResource.multipleWarning] Multiple last resources have been added to the current transaction. This is transactionally unsafe and should not be relied upon. Current resource is org.jboss.resource.connectionmanager.TxConnectionManager$LocalXAResource@6c4a07 ----------------- As I could see JBossTS does not allow more than one 1PC resource per transaction. Two datasources pointing to the same database are considered two resources. Right? My plan of action here is to enable the LRCO(last resource commit optimization) at first, and then enable XA at Oracle and convert our datasources from local to xa. What do you think of this? Thanks again. Marcelo View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4137879#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...