Bad version number can be any combination of trying to run an older VM with newer classes. e.g. Running Seam on a JDK 1.4 would give this or if you have compiled your classes with JDK 6 compability and run it on JDK 5 it will give problems. in any case, when you get deployment errors it should show you higher up in the stack/log what is the root cause. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4119844#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...