If you set "loaderport" on the server, it will create a special purpose server that can be queried for classes. If you set "loaderport" on the client, the built-in classloader will attempt to contact that special purpose server if it can't find a class locally. If you put "loaderport" in the InvokerLocator, both the client and the server will see it. You don't need a custom classloader or custom unmarshaller. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4185289#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...