Unreal Tournament Permission Problem???

I am trying to run the game Unreal Tournament as a regular user but am having problems. I can run successfully as root though. When I try and run as a regular user I get the following error messages in the startup xterm: <snip> Initializing Glide... gd error (glide): Permission denied Couldn't change I/O priveledge level. <snip> Where would I go to fix this???? Gerry