I read something about "switch user". I try this just now. I use Suse9.2.
There is a KDE-Menu-Entry which this name.
in the KDE-Help-Center this is prescribed in 1.1. Desktop Components/1.1.1. The Desktop Menus: "If you right-click the desktop, a more complex menu is displayed, allowing you to customize your desktop. ... ‘Start New Session’
This menu opens a dialog box asking if you want to start a new user environment. ..."
It starts a new X11-Server??? and I could login again.
Switching between the two sessions is possible: Ctrl-Alt-F7 or Ctrl-Alt-F8.