bug#7320: Confirmed on coreutils-8.4-13

[Marc W. Mengel]

This is still broken in RedHat in coreutils-8.4-13

All of  "groups" and "id" and "id -G" report groups that you don't have
if you list a new/different primary group in /etc/passwd.
This is just plain wrong.  "id" and "groups" should list the groups you
actually have, not what you would possibly have if you logged out and 
back in again.