Exchange ActiveSync Functional Specifications?

[stannenb]

We're beginning to evaluate Zimbra's support of mobile devices, and are having trouble establishing a set of baseline functionality.

There are differences created by the clients (Palm vs. Windows
Mobile 5 vs. Windows Mobile 6), the EAS implementation in the cient, and
the server implementations (Exchange 2003 vs. Exchange 2007 vs.
Zimbra).

Marketing material seems easy to come by, but a matrix of
functional specifications is not something I've been able
to find anywhere.

Does anyone have any pointers or suggestions?

Thanks in advance.

[stannenb]

To partially answer my own question...

The folks at Openchange.org have partially reverse engineered
the protocol:

Main Page - OpenChange wiki

[openchange]

Maybe a little bit more than just partially
Funambol,OpenChange,Sogo,Zarafa where will Zimbra fit in? Does it still want to play?

Would love to hear from you guys being that you're at least 4 years invested in Zimbra already? (unless you've switched sine 2008...)