Is there an open source application that can download e-mails from a generic POP mail server, keep a copy of the mails locally and then deliver copies to multiple accounts on a LAN? I have a friend who uses a group e-mail account, and more than one person is always hooked onto that account. The problem is they cannot leave e-mail on the server, as it eats out their webhosting space, but if someone downloads a message in Outlook, the other users do not see that message.
The real problem, however, is sharing a single mailbox. All current mail servers support pointing a single alias (for example,