x-Tip -- Libranet - http://forum.libranet.com/viewtopic.php?t=8391

To fix the xhost error you see sometimes when you try to run a program as root from a terminal:

edit your /etc/kde3/kdm/Xservers file
On the line that says:
:0 local@tty1 /usr/X11R6/bin/X -nolisten tcp
Change it to:
:0 local@tty1 /usr/X11R6/bin/X -ac -nolisten tcp

....
However, the -ac option (per man 1 Xserver) gives access to your display to any host on the local network. Maybe not that great for security.

Another solution is to run

Code:

xhost +local:

after logging in.

This would limit such access to users on the local machine.