The community project z-push and its backendzimbra is quite a nice solution for SOHO zimbra users.

I fielded a question the other day for a Blackberry user who wanted to just somehow get his mail on his blackberry but was totally unaware of the BIS offering from his cell phone supplier. And that got me thinking more about z-push and

At the hypothetical level, I was thinking that a RIM BES server connected to MS Exchange via the MAPI protocol. This led me to think of these products and how to OSS link them to Zimbra.

BESx <---> (proxy server)

Does BES speak to MS Exchange via MAPI?

If so, on the backend does IMAP. So this led me to think <----> zimbra

This opens (pardon the pun) a whole can of worms here if an proxy server sits between BESx and MS Outlook clients on the front end while Zimbra sits on the backend.

i.e. BESx <-----> <-----> Zimbra
. . . . MAPI Protocol to IMAP Protocol conversion

- and - or -

i.e. MS Outlook Client <-----> <-----> Zimbra
. . . . MAPI Protocol to IMAP Protocol conversion

Some technical guru's may fill in some of the finer points here but I believe Redhat has already bundled some kind of MAPI protocol (hack?) with their product. It certainly seems plausible.

Have at it.