hi thanks for the answer. unfortunately i am really new to jboss and therefore have a little difficulty finding my way around so just to make sure I get it right this time. (I've already spent hours trying to figure it all out) i guess classloading isolation can be enabled like this: http://wiki.jboss.org/wiki/Wiki.jsp?page=ClassLoadingConfiguration for jndi lookup I have to create a seperate entry into the -ds.xml config file and then have to make the appropriate changes to the persistance*.xml files as well as to the jboss-beans.xml file. in order to not have conflicting uris i have to probably change the context-root element in the application.xml file am i missing anything? thank you for your help stefan View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4086598#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...