I have noticed over the last year or so that the fglrx driver continually adds and drops support for various chipsets. My idea to overcome this issue of ever changing support, rather than dealing with it the way we do nVidia, is to add a function to AVWizard_Run.sh which, prior to throwing the fail to setup x whiptail, again checks for ATI in lspci, and swaps the fglrx entry with radeon in xorg.conf.pluto.avwizard, and cycles the test again. I did this before when testing all of the ATI crap I have, and it worked well. One of the two fires everything I could get my hands on, but of course fglrx is preferred.
I also have some half written code somewhere which attempts to unlock VAAPI accelleration for 1004+. I will dig that up and start a ticket.