Restrict the mail users to passwd and decouple the mailboxes from the system user
The users are only meant as a way to change the mail password and
setting up forwarding (~/.forward), the latter will be handled by the
DevOps team now.
The homedir is now /home/vmail/%d/%n instead of /home/$USER.
Preparation for switching to a virtual user setup and removing all the
staff users from mail.a.o.
Edited by Kristian Klausen