[exim] MsExchange ---> Exim

Hello,
I want to _change_ MsExchange to Exim in my corporation. I have 150 users in
my network. They work in Outlook 2003. We are using Active Directory to
authentification. Could you tell me what is the consequencies of making that
change.

Especialy I would like to know:
1. Is Exim cooperate with Active Directory or eDirectory? Anybody use Exim
with AD or eDirectory?
2. I know that communication between Exchange and Outlook is with MAPI
protocol. Does Exim use the MAPI protocol?
3. If 2 is no, Is Exim POP or IMAP server? I would like to use POP or IMAP
protocol instead MAPI.
4. Is this possible that Exim has a "Outlook calendar" feature and other
"Outlook like feature".
5. Does Exim support TLS, SSL?
6. Does Exim support acces via http to mail box?

Thanks
pch0317