Mods are automatically logged out on exit

[NSeXcellent]

I have been having some trouble with roommates of moderators, or friends whose homes that moderators go to, and log in, but dont log out. Recently i've had a bunch of members get banned because of a moderator not logging out of his name when leaving a computer terminal. Is there a simple way to change moderator usergroups so that when the forum is closed, their account is logged out everytime??