Hello Imellis85, I know this was posted a long time ago. Could you tell me how you resolved your issue. I am having a very similar problem where in I am migrating my J2EE application from 4.0.5.GA to jboss 4.2.2.GA I changed the necassary jbossall-client.jar file needed for compilation. There are no errors and as I see it no code changes are required. But it pops up the following error when I try to remotely access all the EJB2.1 I have on the server. javax.naming.CommunicationException [Root exception is java.lang.ClassNotFoundException:org.jboss.invocation.unified.interfaces.UnifiedInvokerProxy (no security manager: RMI class loader disabled)] at org.jnp.interfaces.NamingCOntext.lookup(NamingContext.java:668) at org.jnp.interfaces.NamingContext.lookup(NamingContext.java:520) at javax.naming.InitialContext.lookup(Unknown Source) If you or anyone else can shed some light on this matter, it would be most helpful. pc View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4156160#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...