[Exim] EMSD

I have searched the list archives and I have found little about EMSD. If I understand things correctly, EMSD is a recent protocol (RFC 2524) designed for pushing messages to mobile devices. The underlying itch is finding an open source alternative to the RIM/Blackberry wireless messaging product in the US.

So I have a couple of questions about all this: (1) is my understanding correct?; (2) if so, is EMSD a worthwhile alternative?; and (3) is support anticipated in Exim 4?