Robert Cooper wrote:
(er...meant to send this to the list....)
One thought, since I'll be doing this conversion once I get my new mailserver in place...
Since I've only got 3-4 users, I'm planning to just open IMAP mailboxes on both servers in Thunderbird, and drag the messages from the old server (using mbox) to the new (using Maildir). However, It would require two boxes, or two IMAP servers running on different ports, and would not be sufficient for more than, say, 5-8 users.
Now, they may have improved this since, but I found when migrating mailboxes this way with Thunderbird it wouldn't reliably move more than one folder at a time. However, since then both Thunderbird and Dovecot have had several releases.
I would recommend you copy your existing mails to local folders (the ones set up by default in Thunderbird, that you can't delete without manual file editing) and then onto the new server.
This was successful for me in migrating about 20 to 25 users from "locally stored, retrieved from POP" to "joyous IMAP"... and we've never looked back. :)
RobertC
-- Curtis Maloney