Confirm that it worked

$ fglrxinfo
display: :0.0  screen: 0
OpenGL vendor string: ATI Technologies Inc.
OpenGL renderer string: MOBILITY RADEON 9700 Generic
OpenGL version string: 1.3.5461 (X4.3.0-8.19.10)

If it didn't work, you may need to run:

# mkdir -p /usr/X11R6/lib/modules/dri
# ln -s /usr/lib/dri/fglrx_dri.so /usr/X11R6/lib/modules/dri

Thanks to Maciej Matysiak for the clear debug here and solution here.

If it's still not working, try:

# rm /usr/lib/libGL.so*
# rm /usr/X11R6/lib/libGL.so*
# cd /usr/X11R6/lib
# cp /usr/lib/fglrx/diversions/lib/libGL.so.1.2 .
# ln -s libGL.so.1.2 libGL.so.1
# ldconfig

and confirm that 'ldd /usr/bin/fglrxinfo' is pointing to the right one.