Hey genman Thanks for your reply. 1. I know everything i need now :) 2. In this case that is not a very big problem, merge file is not big. Better think that even when we have to write merge files, often we don't have to write all we need ourselves, anly a part. But hmm... not in this case. 3. Your answer to my question is clear for me. And i see the difference now, after removing line from my jboss-service.xml file: <attribute name="JndiName">ResourceName</attribute> | This line was the reason why i couldnt see persistence in action. Everytime i deployed my xmbean my attribute got a default value. But still i need a small clarification or confirmation: Persistence applies only to situation when we redeploy our mbean or restart server? And where jboss stores persistence state for mbeans? I stopped my server and deleted all files from 'server'/tmp/deploy drectory, but after started server again the attribute of my mbean had exactly the same value like before. Best regards vitor_b View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4022979#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...