I have the following model: A class A has a reference to a class B. B has several subclasses including C. Relation between A and B is Lazy. When I get an A instance from the DB, I invoke the getB() method if A class and then I cast the B instance into C in order to invoke a method that only exists on C instance. For B and C I use a Single inheritance. | lazy | A---->B | Î | C(extends B) | getX() | When I cast the getB() instance I have a ClassCastException because getB() is a javassist proxy instance on B and not on C. My workaround is to switch A/B relationship to EAGER but I really like to keep it lazy. Is there some workaround for this proxy issue ? (that's the same issue with CGLIB). Is it a know bug ? View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4084463#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...