It's good to have the two of you in the same place, I'm trying to make sense of this problem and haven't been able to reproduce it as of yet.
It'd be good if you, both, could post detailed information about your system's hard and software (including AGP aperture size). Hopefully this will help somewhat.
I'm assuming you're using FreeBSD -STABLE and have tried the basic sanity precautions mentioned in the FAQ hosted by the NVIDIA petition people (i.e. building without optimizations, etc). I understand that all you need to do is start UT2003 to trigger this problem?