[Exim] Qmail Convertion

I have recently switched from Qmail to Exim in order to use cpanel. I
have some users that need their mail moved over from the Qmail system to
the Exim system. The mail boxes are of different formats and I have
been unable to find any documentation about how to convert the mail
without using a POP or IMAP client which I can't do. Can someone help
me with this?

Thank you,
Chad Stephens