Fedora :: Sharing Email And Address Book?

I want to share 3 email addresses and an address book among 2 users on a small network with 3 computers. Emails come from 3 different POP email accounts. There are 2 users.Each user may use any of 3 computers on the network (2 computers are linux, one is Windows XP). The 2 users have separate userids on the linux machines, but share an account on the Windows machine.

Each user should be able to view, reply to, delete, and otherwise deal with emails from any of the 3 POP sources, regardless of which computer the user is logged on to. Also, each user should be able to view and update entries in the address book, regardless of which computer the user is logged on to. What about using a system like courier or egroupware to retrieve and store the email from the 3 POP sources? Then courier or egroupware could make its mail store (maildir?) available via IMAP to the 2 users via email clients on each of the 3 computers.

The mail would be stored in the single, unique, courier or egroupware maildir store, not in the email clients. So if any user deletes a message or replies to a message, the action is visible to the other user from any computer. Also, emails only need be deleted once, not multiple times from each email client. I have looked at the courier and egroupware documentation, but I can't figure out whether either of them can be set up to retrieve email from 3 POP sources? If they can, how do you do it?

They appear to be email servers that collect emails sent to the domain they are configured to serve? could email clients be setup to share a single mailbox and address book (at least on the linux machines. forget about Windows). I guess the mailbox would lock when any client opened it, so only one client at a time could be active.