I packed my classes in three files: business.ejb3, entity.par and web.war, then pack them all in one EAR, finally successfully deployed in JBoss 4.0.3, it works fine. But later I used a class A which is packed in business.ejb3 as parameter for a session bean which is also packed in business.ejb3, then the session bean can not be deployed, it says the class A can not be loaded. But if I did not use A as parameter, it works fine, strange, what happened to the EAR/EJB classloader ? Anybody has met this kind of issue before? Thanks a lot.