Removing the classes12.jar did not seem to HURT anything per se, but it did not resolve the ClassCastException View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4127132#4127132 Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&p=4127132