Since this has happened more than one time, I guess there should be a solution for the problem: http://www.jboss.com/index.html?module=bb&op=viewtopic&t=146554 http://www.jboss.com/index.html?module=bb&op=viewtopic&t=146001 The jbossall-client.jar is needed if I like to run my EJBs on the jboss application server. But since jboss as uses aop for his own purposes the jbossall-client.jar has its own version of the AspectManager included. The result is that you have two different AspectManager versions in your classpath. So it depends on your classpath order if the right AspectManager is used. In my opionion that is not a desired situation which should be fixed somehow. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4194607#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...