on the subject of overloading: __call()

was there discussion about the interaction of __call() and methods which declaring their arguments as references? there's no way at present to make this work, as far as i can tell. seems like it could just be a documented limitation, but i thought i'd check. related topic: in the current state of ze2, there are several ways to call methods directly that can't be emulated by call_user_func() - calling self::method() for instance, or the visibility of $this if you call class::method(). is that likely to stay true?