This problem was solved by replacing @Id annotations in Entity B with @EmbeddedId and @Embeddable constructs View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=3986841#3986841 Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&p=3986841