The XIDFactory is a red-herring. It is only used when it is configured with an XAConnectionFactory and it knows it is going to eventually use 1PC, i.e. there will be no other resources in the transaction. This will be true for BMT or CMT/NotSupported. In this case, it optimizes away the JTA transaction and drives the "transaction" itself. All it needs is a mechanism to generate unique XIDs so it can control the XAResource. Using the XIDFactory from JBossJTA is one mechanism, but not necessarily the cleanest, especially when we are moving to JBossTM for JBoss5 anyway. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=3968637#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...