In the KDE Control Center, click on System Administration -> Login
Manager and then select the "Convenience" tab.  Click the button for
"Administrator Mode" and enter the root password.  Then enable
Automatic Login for a user.

In theory, the system should automatically log this user in the next
time the KDE starts.  However, this doesn't work for the following
reasons:

1) The /etc/X11/prefdm refers to the /usr/sbin/autologin program,
which we no longer ship.  

2) The autologin feature does not work with gdm...only with kdm.  The
problem is that to enable kdm, the user has to manually add
'DISPLAYMANAGER="KDE"' to /etc/sysconfig/desktop.


So I think that there are a few parts to fix this problem. 

1) Remove the autologin part from /etc/X11/prefdm since it's obsolete
(bug #108969)

2) One of the following:
   a) Have the KDE Control Center make the necessary changes to
/etc/sysconfig/desktop to start kdm, or
   b) Have the KDE Control Center pop up a dialog telling the user how
to manually change /etc/sysconfig/desktop to start kdm, or
   c) Make gdm allow the autologin feature to work, or
   d) Remove the autologin tab from KDE Control Center altogether

The current behavior is a bug in that it appears to the user that
autologin will work after selecting the autologin options, but there
are more hoops to jump through before autologin will actually work.