[Dovecot] different configurations for individual user

[Joshua C.S. Chen]

Hi everyone,
  I am planning to upgrade my current uw-imap to dovecot. I am using Linux 
(Redhat EL 4). The main purpose is to use maildir instead of mbox.
  For some reason, I don't want to upgrade all users' mail boxes all at a 
time, but I want to change the imap server first (to dovecot), while keeping 
all mbox files, then convert them to maildir user by user (one user at a 
time). My question is:

Is it possible that dovecot can setup individual user's own configuration? so 
that some users can setup mail_location = mbox but others = maildir.


Thanks in advance
Joshua