[Dovecot] strip realms and force lowercasing of usernames?

[Dan Hollis]

Is it possible for dovecot to strip realms and force lowercasing of usernames?

We have a lot of dumb customers who try logging in to pop3 with crap like 
UsERNAmE and bla at nonexistentdomain.com. All our usernames are lowercase 
and we have no realms. Trying to get hundreds of customers to fix this is 
hard and is a significant and costly support burden.

It would be nice if dovecot could handle this in some way.

-Dan