If I were them, I'd try deploying their existing EARs/JARs on each platform and see where the differences lie. Given that they've got some time before their deliverables, I'd try to get on the AS5 train early as possible. 4.2.2 is certainly more stable, but they want to be developing alongside our own releases to stay in line incrementally instead of worrying about a large migration later. Also good news for this type of scenario is that we'll soon be allowing existing AS installations to upgrade EJB3 without the entirety of the AS (via our new/reinstated Plugin Installer). Where are you giving the training? S, ALR View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4134404#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...