Auto expunge log

[Michael Ludwig]

Hi,

I'm just setting up a new dovecot system and wonder why I get this
error. On another dovecot system this works with no problems.

Log entry when exiting MUA Thunderbird:
===========================
Nov 16 20:16:35 myhostname dovecot: imap(info at mydomain.de): Error:
autoexpunge: Couldn't create dovecot.autoexpunge.lock lock:
file_create_locked(/var/mail/vmail/mydomain.de/info//dovecot.autoexpunge.lock)
failed: safe_mkstemp(/var/mail/vmail/mydomain.de/info//dovecot.autoexpunge.lock)
failed: No such file or directory
===========================

Is this double slash between /info//dovecot.auto... okay? I believe
there should be a "Mailbox" in between?

Configuration in /etc/dovecot/conf.d/15-mailboxed.conf
===========================
namespace inbox {
  mailbox Junk {
    auto = subscribe
    special_use = \Junk
    autoexpunge = 90d
  }
===========================

Maybe you can help me a bit. ;-)
Michael