That is what we know so far:
The Radeon HD series has Driver issues with all id-tech3 based games.
Assuming this issue has been fixed, perhaps the id-tech3 engine with rituals Übertools has been forgotten, how ever, you should contact ATI Support about this issue, the games have been released quite a few years back and have not been changed since then.
If it is a Übertools related issue, you should have issues with all the game
listed here.