Glassfish has a very different classloader than JBoss and Tomcat. Perhaps you should consult to the Glassfish team. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4126413#4126413 Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&p=4126413