[ Thanks to Michael Larabel for
this link. ]
“With no public release of the Catalyst Linux driver
supporting X Server 1.5, any user trying to load the driver will
run into show-stopping problems due to the ABI breaking. Simply
put, the Catalyst driver will not work with any distribution using
this new version. In the meantime, users are forced to use the
xf86-video-ati or xf86-video-radeonhd drivers or even the VESA
driver if one of these two open-source ATI drivers
fail.”