Ask in the portal forums. Looks like a mismatch in hibernate/cglib/objectweb codebase. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=3958125#3958125 Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&p=3958125