Permissions issue with Debian 8, dovecot 2.21, vpopmail

[Stephen]

There is a permissions issue in dovecot 2.21 in the ~/run directory 
(mine is /var/run/dovecot) at least in Debian 8.

Files created by dovecot imap:

srw------- 1 root    root 0 Feb  3 16:46 imap-hibernate
srw------- 1 root    root 0 Feb  3 16:46 imap-master

changed to make work:

srw-rw-rw- 1 root    root 0 Feb  3 16:46 imap-hibernate
srw-rw-rw- 1 root    root 0 Feb  3 16:46 imap-master

Errors were reported in /var/log/dovecot.log which we use mainly for 
fail2ban (it gets huge, but ...)

vpopmail version 5.4.33 with one patch

I don't think this is a Debian issue ... possibly could be a vpopmail 
issue, but it's probably caused by the fact that imap daemons are 
running as vpopmail:

vpopmail 30182  9187  0 15:02 ?        00:00:00 dovecot/imap