Thank you very much Norman, I had indeed in my persistence-dev.xml the following line in 1.1.6 : and in 1.2.1 So for the moment I change the value of the "value" attribute to update and it's working. I don't know if it's the good choice but I don't know very well hibernate, I used to develop with OJB. ;o). Thanks again. Christophe. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4034404#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...