In my last topic http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4105325 , I found jbossall-client.jar conflicts between 421 and 422 AS, that's a serialVersionUID bug. And I continue to test other version clients for Jboss 422 AS, and still have problem in Jboss 405 case. I use the flag -Djboss.remoting.pre_2_0_compatible=true on the JBoss 4.2.2 side to interoperate with Jboss 4.0.5GA client, and the client can call 422 EJB3 successfully. But after that, I found another client using 422 jbossall-clent.jar can not call the EJB3 any longer, the following exception occured: | javax.naming.CommunicationException [Root exception is java.io.InvalidClassException: org.jboss.remoting.InvokerLocator; local class incompatible: stream classdesc serialVersionUID = -2909329895029296248, local class serialVersionUID = -4977622166779282521] | at org.jnp.interfaces.NamingContext.lookup(NamingContext.java:780) | at org.jnp.interfaces.NamingContext.lookup(NamingContext.java:627) | at javax.naming.InitialContext.lookup(InitialContext.java:351) | ...... | And I remove the flag -Djboss.remoting.pre_2_0_compatible=true, it works fine, of course the jboss 405 client failed as well. It seems that when using -Djboss.remoting.pre_2_0_compatible=true, the jboss remoting 2.0 becomes incompatible with 422 AS, I think that's a bug of jboss 422, maybe a jboss remoting bug also. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4105757#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...