Assuming all of your JVMs came from Sun, and are at the same release level (e.g., all 1.5.0_10) they should all behave the same. Therefore, without a stack trace showing the problem, it is impossible to diagnose (for example, I could assume you are getting a class not found error and give you ways to correct that, but if that is not the error you are getting it would do you no good). Also, if the error in a stand-alone client application, or is it happening within the application server? View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4020657#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...