[Dovecot] Virtual users vacation notices and forwards

[Del Stoliker]

I'm in the process of moving from UW-IMAP to dovecot. I'm exploring the idea
of using virtual users with dovecot and storing all user information in
LDAP. While bouncing this idea off of a coworker, he asked me how we could
handle vacation notices and forwards. Currently, we're using a procmail
recipe to generate the vacation notice, and the sendmail .forward file for
forwards (although most of our forwarding takes place elsewhere so the
.forward file is rarely used). These are, of course, dependant on the user
having an account on the mail server. How are those of you using virtual
users supporting this functionality?

Thanks!