I finally found the solution for my problem. I had to put the javassist.jar and jboss-aop-jdk50.jar in my WEB-INF/lib folder to make it work. This was a lot of trial and error going on here, so I would be delighted if somebody could explain why this happened to be the (a) solution. Also why is this not documented, because I use the refdocs on a clean JBoss AS. Just to understand what's going on. Thanks in advance. View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4258676#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...