Why do you believe you need this support? JBossTS, like other commercial-grade/enterprise transaction systems, supports the TWO-PHASE COMMIT protocol. This means participants need to understand the prepare/commit/rollback messages they will get from the coordinator. Now obviously not ever participant in existance is 2PC-aware. In that case, as with other products such as Tux and CICS, we support LRCO. This allows a single 1-phase aware participant to be enlisted with a two-phase transaction as long as it is handled correctly within the protocol. If it isn't, or if you try to add more than one 1-phase aware participant, then you will potentially end up with non-atomic behaviour. Believe it or not, but that's not a good idea. Heuristic outcomes are bad enough, but at least with them you have durably recorded the results and can attempt some form or resolution, even if manually. There's a really good book on the subject: http://www.amazon.com/Java-Transaction-Processing-Implementation-Professi... So rather than rush into supporting something like this, I'd prefer to see a discussion about why it is needed in the first place. If there's a real need then we can consider it, but definitely a case of caveat emptor! View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=3988768#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...