[Dovecot] auto-detection of user mailbox type

[John Harper]

The config file indicates that if mail_location is empty, dovecot will
try to find the mailboxes automatically (and by implication determine
if the user is using mbox or Maildir format). But if the mbox inbox is
non-standard (I have procmail delivering to ~/.mail) then one needs to
specify

 mail_location =  mbox:~/mail:INBOX=~/.mail

and presumably dovecot will no longer try to determine what each user
is doing. 

I'd like to slowly convert users from mbox to Maildir (putting
DEFAULT=Maildir/
in the users' .procmailrc accomplishes that from the delivery side)
and have dovecot still automatically figure out which way to work,
based on finding ~/Maildir (or not). Somehow I don't think 

 mail_location =  maildir:~/Maildir:mbox:~/mail:INBOX=~/.mail

is going to do what I want. I saw the example on multiple mailboxes
using namespaces, but I confess I'm not clear on that especially with
ragard to the INBOX setting.

I know I can set mail_location on a per-user basis using the userdb
(eg ldap) but was hoping to avoid that. Is there a way to specify the
details of the mbox configuration, but have dovecot instead use
Maildir if that exists?

Thanks,

John Harper
-------------------------------------------------
Senior Systems Administrator
Information and Instructional Technology Services
University of Toronto Scarborough
harper at utsc.utoronto.ca