The behavior you are seeing with "merge" is correct. It takes a detached entity and merges it into the DB. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4016806#4016806 Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&p=4016806