Suse 12.1 Changing Display Manager

To change display manager (xdm,gdm,kdm), you only need to edit /etc/sysconfig/displaymanager file.

## Path: Desktop/Display manager
## Description: settings to generate a proper displaymanager config
## Type: string(kdm,xdm,gdm,wdm,console)
## Default: ""
## Config:      xdm,kdm,gdm
#
# Here you can set the default Display manager (kdm/xdm/gdm/wdm/console).
# all changes in this file require a restart of the displaymanager
#
DISPLAYMANAGER="kdm"