I hadn't tried reproducing this so far. Today i got this reproduced on JBoss-5.0 GA. The issue happens in the following scenario: 1) Your application is packaged as EAR 2) Your application has a jboss-app.xml with classloader configuration (does not matter whether it is java2ParentDelegation=false or java2ParentDelegation=true) 3) You have an EJB in which there is a @Resource injection happening for a application specific type (i.e. the class/interface belongs to your own application) In this specific scenario, you see this ClassNotFoundException. This is a bug. "jhsingle" wrote : | There was one other bean with self-injection and I had changed that one also before my last post. Just to be sure, here's the code for WorkflowEngine with the self-injection removed: I am sure there's definitely some other place where the @Resource injection of application specific class is happening. Are you sure you deployed the fresh files (cleanup existing ones from JBoss). "jaikiran" wrote : | The code which you posted, shows self-injection | Based on the test case that i have, this has got nothing to do with self-injection. Injecting resource of type myapp.A into myapp.B manifests this problem. Possible workarounds: 1) Probably the easiest - Remove all @Resource injection of application specific classes OR 2) Deploy the application as a standalone jar instead of EAR. The problem does not arise in a standalone jar OR 3) Do not configure classloading through jboss-app.xml - You can leave that file empty or remove it. From what you posted, i see that you are not using this jboss-app.xml for anything else. View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4200639#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...