Hi Jaikiran, Thanks for the hint. I searched and found the error report for that issue, but didn't know, what exactly had to be done. Well, I did what you said, but it didn't work. I also tried your earlier suggestion to avoid deployment with eclipse and use ant instead. I used the script of the EJB 3 book cited, since this work with the current Jboss installation - but they all result is the same error. In the meantime I spent so much time on this, that I'm a bit desperate. I'm thinking of trying once your other suggestion and try again with a newer version. Which combination of eclipse and Jboss would you recommend as being most stable? Thanks for your help Markus View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4159581#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...