Thank you very much jaikiran, this is exactly what I was trying to do, but I had a hard time explaining it. The reason why we use a different resource-name for the datasource in our EJB code than what is defined in the -ds file is because our application is customizable and need to be deploy using different databases for different clients. The way we did that is to define a bunch of different datasource JNDI in the -ds file (like app-specific/datasource) but map all of them to the same reference datasource in our code (app/datasource). That way our EJB code remains generic. The explanation about Web environment vs EJB environment makes total sense, although this is not something I would expect to change from 4.X to 5.0 ;-) I will try to add the missing EJB references this week and see if it works. Thanks again for all the comments! View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4143709#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...