"nope...the only tabs in Login Manager are appearance, font, background, users, convenience."
Wierd. On Fedora Core 1 I have Appearance, Font, Background, Sessions, Users, Convenience. I ran SuSE 8.2 until November and I think I remember Sessions as being where I described it.
The next place to look is in Yast. Perhaps SuSE moved the function to someplace in Yast.
Be prepared. Create a LifeBoat CD.