Daniel, Thanks a lot for the answer. The 'confusing' thing is that this application works without any problems when running with 'java' but not with 'javaws'. So I was just wondering maybe somebody encountered this problem with web start and has a workaround/solution. Of course upgrading the JBoss is an ideal solution but its not that easy in my case. View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4212713#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...