In my case, I used UW IMAP under Linux, for years This built up a huge mailbox repository of valuable data. As I migrated to 10.3 Server and Cyrus/Postfix, I saw the need to move all that data over cleanly and safely.

My first attempt was that of mounting both IMAP servers, Linux and Cyrus, via Mail.app. Then dragging mailboxes across. It all seemed to work, especially for those small mailboxes. However, I have noticed that for the large mailboxes, not all messages have transferred.

Any other suggestions?

Thanks in advance.

-otto