Migrating from Local Database to OpenDirectory, and Migrating IMAP Boxes

Question

I have a Xserve G5 running 10.4.11 and using a local (non shared) directory with all of my users on it. I'm planning to install a new Xserve (10.5.2) to use as a Fileserver and Filemaker Server, essentialy leaving the mail service to the G5. However, i want to use the OpenDirectory on the 10.5 server in order to maintain only one user database. I'Ve tested out the functionnalities and it looks like that there is no problems using the 10.5 OD with my 10.4 server, however, since 90% of my users are using IMAP mailboxes, i cannot migrate the database to the new users
Example:
On the local directory of the 10.4 server, i have a user called Wiggum using IMAP mailbox, working fine. I tell my 10.4 to use the OD on the 10.5 server (user Wiggum already configured over there with the same settings, passwords) and when i remove the user from the local directory, leaving only the OD, the user is working OK, mail is working fine but i loose all contents of my IMAP box, i get only the new mails.
Is there a way to migrate the IMAP boxes from the users on the local directory when i migrate them to the new OD.

Answer 1

I would think the first shortname is different in OD vs. the local user. Thus, creating a second mailbox and this is why you see only new incoming mail.
Check if you have "duplicate" mailboxes. If yes, you could copy mail from one to the other and reconstruct the mail database.