I finally found the relevant bit in the specs: EJB 3 Persistence 5.6.2.1. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4008415#4008415 Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&p=4008415