bug in group permission check

[krzf83@gmail.com]

Jul 19 01:05:27 sv1 dovecot: auth: Error:
passwd-file(aa at ddd,89...24,<>):
stat(/usr/dovecot-cfg/dom-home/ddd/etc/ddd/shadow) failed: Permission
denied (euid=33454(dovecot) egid=33454(dovecot) missing +x perm:
/usr/dovecot-cfg/dom-home/ddd, we're not in group 33795(sysgroup), dir
owned by 32072:33795 mode=0710)

root at sv1 [~]# sudo -u dovecot groups
dovecot sysgroup

root at sv1 [~]# sudo -u dovecot cat /usr/dovecot-cfg/dom-home/ddd/etc/ddd/shadow
<prints content of the file>

It seems that dovecot incorecly checks for group permissions not even
trying to access file - probably cant handle that dovecot is part of
more than 1 group. When its part of single group problem is not
occuring.