I think that the idea of having an API to check the versions is a good one. I recall many years ago while developing a client/server app that one of my testers complained almost daily that the build was broken. After a few times of helping him and finding out that in each case he mismatched the client and server components, I added a method to the server that returned the version number, and had the client request the version number before doing anything else, and generating a decent error message if it did not like what it saw. That tester never complained again, though he did mention that he often got that error but now at least he knew what he did wrong and how to fix it. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4200139#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...