I think you are "loosing updates" because you trigger several stateless session-beans in parallel (very often and fast) ... So you have concurrent access to your data --> I was assuming, that you will get an exception telling you that you have the wrong version to update the object - unfortunatelly I don't know what's going on with your exception that you got. I know it works, because we have also concurrent calls - and we get nice exceptions in case of two "threads" are manipulating the data ... ... View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=3992746#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...