"PeterJ" wrote : The jboss-messaging-client.jar file is only for use with a stand-alone messaging client. You do not need it for a messaging client that is deployed to the application server. All of the necessary classes should already be in the jar files in the server/default/lib directory. Thank you for the reply! But I don't think the messaging classes are available on the server side though. As I mentioned in the first post, I got ClassNotFound exception when trying to retrieve the queue object. This is because the JBoss Messaging is deployed in scoped classloader. Further, I think the classes under the jboss-messaging.sar are missing some classes required by messaging clients. I copied all the jar files under that directory into the server's lib dir and still got exceptions for missing classes. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4005583#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...