imap-hibernate won't start

[Webservice]

I can't get imap-hibernate to fire up.

The process is not starting, and there are no clues in the logs.
I tried several users/groups, but nothing happens (although I see plenty
of IDLE imap-connections).
Even mode 0666 didn't work.


I'm on Slackware (no FreeBSD), built from source with
 ./configure --with-mysql
My systems runs with a virtual user, and imap-processes are run under vmail

vmail  21840  0.0  0.0  14076  2596 ?  S  01:11   0:00 dovecot/imap
vmail  21842  0.0  0.0  14108  2568 ?  S  01:11   0:00 dovecot/imap

I see the socket in var/run/dovecot with OK-permissions:
srw-rw---- 1 vmail dovecot     0 Mar 14 01:11 imap-hibernate=



Added in my config:


mail_debug = yes
verbose_proctitle=yes
service imap {
  unix_listener imap-master {
    user = $default_internal_user
  }
}
service imap {
  extra_groups = $default_internal_group
}
service imap-hibernate {
  unix_listener imap-hibernate {
    user = vmail
    mode = 0660
    group = $default_internal_group
  }
}



Can someone give me a clue where it's going wrong?
Or an option so I can debug?