I found I must include the JBOSS_HOME\client\jbossall-client.jar into the client's classpath. But previously I copied the jbossall-client.jar from JBOSS_HOME\client to my Myeclipse project, and includes this copy to my client's classpath, this dosen't work. Can anybody explain why I must include the JBOSS_HOME\client\jbossall-client.jar instead of a copy? In an application, normally the client wouldn't be at the same machine as the server, so the client couldn't include the jbossall-client.jar at the server side, that's why I made a copy of jbossall-client.jar from the server. View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4221759#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...