Comment 2 for bug 511295

This leads to another effect: the dovecot deliver command may complain like this "Fatal: postmaster_address setting not given". The problem is, that dovecot's deliver command defined in master.cf needs the -c parameter too:

dovecot unix - n n - - pipe
  flags=DRhu user=vmail:vmail argv=/usr/lib/dovecot/deliver -c /etc/dovecot/dovecot-postfix.conf -f ${sender} -d ${recipient}