Hi Clebert/Tim, I did check the class dependencies and found all the classes in jboss-remoting.jar or jbossall-client.jar. I have tried putting the jboss jars in Sun AS classpath perfix but the same exception happens: /logicalhost/is/lib/jboss/jboss-aop.jar /logicalhost/is/lib/jboss/jboss-remoting.jar /logicalhost/is/lib/jboss/jbossall-client.jar /logicalhost/is/lib/jboss/javassist.jar /logicalhost/is/lib/jboss/jboss-mdr.jar /logicalhost/is/lib/jboss/trove.jar /logicalhost/is/lib/jboss/log4j.jar I believe the JBAS version is 4.3.0 since all the Jars provided by the vendor is in 4.3.0. I will confirm it with the vendor. On the other hand, if JBAS 5 deprecated jbossall-client.jar, what jar should a client use instead of it? View the original post : http://www.jboss.org/index.html?module=bb&op=viewtopic&p=4224910#... Reply to the post : http://www.jboss.org/index.html?module=bb&op=posting&mode=reply&a...