I have been asked to show my supervisor what a Linux mail server would look / run like. He doesn't want to spend the money to buy Exchange or the massive rebuild of our network to get Exchange working. Here is what he is looking for:
1) global address book
2) easy user management
3) imap accounts
4) easy backup of all accounts, settings, and boxes
If anyone has a good site for a howto or a recommendation for a mail system that would be great. This is a bit over my head so I hope that some one around here can point me in the right direction.