Re: UT2003 fails to run
Xlib: extension "XiG-SUNDRY-NONSTANDARD" missing on display ":0.0".
The above line can be ignored, it simply says you're not running a commercial X server from Xi. No big deal.
OpenGL renderer relies on DXTC/S3TC support.
That line means that your card does not support the S3 texture compression on which UT2003/2004 rely. Chances are you're going to have to get a newer card.