MockControl control = newControl(InterfaceFab.class);
InterfaceFab fab = (InterfaceFab) control.getMock();
ClassFactory cf = newClassFactory(fab);
fab.addInterface(BeanInterface.class);
fab.addMethod(new MethodSignature(String.class, "beanMethod", null, null));
fab.createInterface();
control.setReturnValue(null);