Hi Javid, I can't give you a complete answer, but one reason for keeping them around is for compatibility with older versions of the Application Server. For example, if you wanted an instance of AS 4.0.2 to connect to an instance of AS 4.2.0, you would need a legacy invoker because really early version of Remoting, upon which the UnifiedInvoker is based, aren't compatible with newer versions. Whenever possible, though, you should use the UnifiedInvoker. -Ron View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4127275#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...