I fixed my Debian box by commenting out the last line in
Happy tree murdering!
#fglrx 12.4.1 pinned from here for now: 4670 not supported after this date
deb http://snapshot.debian.org/archive/debian/20120515T220710Z/ unstable main contrib non-free
#xorg 1.11.2 from as required by fglrx
deb http://snapshot.debian.org/archive/debian/20111201T040728Z/ unstable main contrib non-free
# fglrx pinned to hold 12.4.1, later versions don't support 4670
Package: *fglrx* xserver-xorg*
Pin: origin "snapshot.debian.org"
#xorg pinned to provide 1.11.2 as required by fglrx
Pin: version 2:126.96.36.1991-1