The dereferencing error usually occurs because your resolution of the component's local reference to the global JNDI object is incorrect. Check jmx-console -> jndiview -> list to check your EJB for correct resolution. As to the first problem, it sounds like you are resolving to the wrong end-point, obtaining the wrong local home. Check your bindings again. We are working in the dark so you might want to post your relevant ejb-jar.xml and jboss.xml for the caller (or web.xml and jboss-web.xml if the caller is a servlet/JSP).
Thanks, I found the Mistake.
I have had the wrong
in the <ejb-local-ref> in the Session-Bean.