A lot. It helps if you can play a level between 1 and 5 minutes in order to advance on my UT install. Otherwise the "moving brush tracker" will cause it to SIGSEGV. I think. That's what initializes last before it shuts down. It gives me no other clues as to the cause. But given the behavior, when I use the mouse, it causes it somehow. I think SDL is at fault, as any other game that uses SDL like lsdldoom also crashes when I use the mouse for mouselook. and i can play lsdldoom with only the keyboard and it runs flawlessly.

Oh, if it helps:
AMD Athlon XP 2000+
327 MB SDRAM
Nvidia GeForce2 MX 400 64M SDR


AGP is working, I checked in dmesg, I've tried recompiling SDL once already, and I'm considering getting a CVS version to see if this helps, but before I do that on my slow as mud internet connection, I might as well ask here first.