Mistake not "@JoinColumn(name = "grupaProd_id")" but "@JoinColumn(name = "client _id")". View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4005718#4005718 Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&p=4005718