Zimbra supports "External Accounts" which will allow you to download mail from remote sources (IMAP/POP) into a specific folder or directly into the user's Inbox..
That being said, you could set up users and set up an external account to pull their mail down from the original server using POP3, and then you would be able to re-host the emails that way. You would also be able to change their Persona so their "From" address is the original email/domain rather than your servers email/domain. |