Comment 31 for bug 855943

But "link group x86_64-linux-gnu_gl_conf is broken" itself is NOT fglrx problem as the same happens even without fglrx installed! Inability to circumvent it or sometimes uninstall correctly may be, of course. I don't have "unbootable" problem, but GL still does NOT work normally on Oneiric, with versions - fglrx, fglrx-updates and downloaded Catalyst (the same which DID work perfectly on Lucid!) - differing in specific failures.

It's about mesa GL packages for Oneiric:
libgl1-mesa-dri libgl1-mesa-glx libglapi-mesa libglu1-mesa
In Synaptic they all are flagged as installed, but "installed files" lists are unavailable because packages are not installed, and an attempt to reinstall any of them causes this very error.