Crash on WinXP but not Win2k

I was fine-tuning some lighting code (work computer: Windows 2000, home computer: Windows XP) and was surprised to find the code caused a nasty crash on WinXP. After isolating the offending code, and referring to the Red Book, I discovered that commenting out:

glMaterialfv(GL_FRONT, GL_SHININESS, mat_shininess);

prior to glEnable(GL_LIGHTING);

in the OpenGL setup code causes a crash in WinXP, but not in Windows 2000.

Any suggestions why? Is Windows 2000 a bit more lax than WinXP?

I can’t see why that would cause the crash, although it might. I would first look at the vid card drivers, I suppose those drivers have more bearing on the effect of ogl function calls. I have heard whispers in the wind that say ATI drivers aren’t as well written as nVidia drivers, but don’t quote me there.