I have a server running qmail with about 300 user accounts on a ubuntu version 8 server. I would like to migrate qmail to a new mta such as exim4.x. I have a VM setup using redhat enterprise version 6 to test the mail migration process. On my VM I installed exim using YuM and also installed courier-imap version 4.x from source. Both services are running. Using the maildirmake command on the VM server I created the exact same list of all of the Maildir directories on the qmail ubuntu (current mail server). I am assuming I can rsync all of the e-mails from the qmail server mailboxes to the new exim system?. on the qmail server openldap is also installed and configured. how can I make the accounts on the new exim VM server authenticate through the openldap server that is currently configured on the qmail server? is this something I need to configure through courier-imap or the /etc/exim/exim.conf file?
I hope I make any sense here. Thanks for your help.