i think the reply above ist correct...
the
ati support page says about removing:
---
Remove existing OpenGL software BEFORE installing ATI drivers
1. Ensure that no 3D OpenGL programs are running
2. Remove the existing libGL installation using the following command:
rpm -e --nodeps XFree86-Mesa-libGL
(You need the --nodeps option because some screen savers, qt-3, and some parts of XFree86 might depend on libGL. Installing the ATI package afterwards will restore these dependencies.)
3. Reinstall the ATI Proprietary Linux driver
rpm -Uh <ati_package_name>.rpm
---