Hello, i 've got an Exception, that OneType is not of type OneType_javassist... in method coerceToType. My workaround (works for me but possible isn't a finest solution) if (type == null || Object.class.equals(type) || obj.getClass().isAssignableFrom(type)) Please check this and describe in some words the problem, if i did a mistake and need an imporovement of model to avoid this problem if a future . Thanks! View the original post : http://www.jboss.com/index.html?module=bb&op=viewtopic&p=4040402#... Reply to the post : http://www.jboss.com/index.html?module=bb&op=posting&mode=reply&a...