package fglrx 2:8.960-0ubuntu1 failed to install/upgrade: subprocess installed post-removal script returned error exit status 1

[Alaroldai]

Observed immediately after upgrading to Ubuntu 12.04 - AMD graphics wouldn't allow multi-desktop extended display (mirroring only). Attempted to change to using the post-release updates option through the "Additional Drivers" program, at which point this error occurred. Now I continually get "system program problem detected" messages, often about one of the amd programs (I think it's amdcccle-something?) exiting unexpectedly.

ProblemType: Package
DistroRelease: Ubuntu 12.04
Package: fglrx 2:8.960-0ubuntu1
ProcVersionSignature: Ubuntu 3.2.0-24.37-generic 3.2.14
Uname: Linux 3.2.0-24-generic x86_64
NonfreeKernelModules: fglrx
.tmp.unity.support.test.0:

.tmp.unity.support.test.1:

ApportVersion: 2.0.1-0ubuntu7
AptOrdering:
 fglrx: Purge
 fglrx-amdcccle-updates: Purge
 fglrx-updates: Purge
Architecture: amd64
CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins'
CompositorRunning: compiz
Date: Sat May 12 11:16:40 2012
DistUpgraded: 2012-05-12 00:36:41,142 DEBUG enabling apt cron job
DistroCodename: precise
DistroVariant: ubuntu
ErrorMessage: subprocess installed post-removal script returned error exit status 1
GraphicsCard:
 Advanced Micro Devices [AMD] nee ATI Whistler XT [AMD Radeon HD 6700M Series] [1002:6740] (prog-if 00 [VGA controller])
   Subsystem: Apple Inc. Device [106b:6740]
InstallationMedia: Ubuntu 11.04 "Natty Narwhal" - Release amd64 (20110427.1)
JockeyStatus:
 xorg:fglrx_updates - ATI/AMD proprietary FGLRX graphics driver (post-release updates) (Proprietary, Disabled, Not in use)
 xorg:fglrx - ATI/AMD proprietary FGLRX graphics driver (Proprietary, Disabled, Not in use)
MachineType: Apple Inc. iMac12,1
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.2.0-24-generic root=UUID=615223e1-9248-4156-9572-f003a4fd13d6 ro quiet splash vt.handoff=7
SourcePackage: fglrx-installer
Title: package fglrx 2:8.960-0ubuntu1 failed to install/upgrade: subprocess installed post-removal script returned error exit status 1
UpgradeStatus: Upgraded to precise on 2012-05-11 (0 days ago)
dmi.bios.date: 01/24/12
dmi.bios.vendor: Apple Inc.
dmi.bios.version: IM121.88Z.0047.B1F.1201241648
dmi.board.name: Mac-942B5BF58194151B
dmi.board.vendor: Apple Inc.
dmi.chassis.type: 13
dmi.chassis.vendor: Apple Inc.
dmi.chassis.version: Mac-942B5BF58194151B
dmi.modalias: dmi:bvnAppleInc.:bvrIM121.88Z.0047.B1F.1201241648:bd01/24/12:svnAppleInc.:pniMac12,1:pvr1.0:rvnAppleInc.:rnMac-942B5BF58194151B:rvr:cvnAppleInc.:ct13:cvrMac-942B5BF58194151B:
dmi.product.name: iMac12,1
dmi.product.version: 1.0
dmi.sys.vendor: Apple Inc.
version.compiz: compiz 1:0.9.7.8-0ubuntu1
version.fglrx-installer: fglrx-installer N/A
version.ia32-libs: ia32-libs N/A
version.libdrm2: libdrm2 2.4.32-1ubuntu1
version.libgl1-mesa-dri: libgl1-mesa-dri 8.0.2-0ubuntu3
version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
version.libgl1-mesa-glx: libgl1-mesa-glx 8.0.2-0ubuntu3
version.xserver-xorg-core: xserver-xorg-core 2:1.11.4-0ubuntu10.1
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.7.0-0ubuntu1
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:6.14.99~git20111219.aacbd629-0ubuntu2
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.17.0-1ubuntu4
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:0.0.16+git20111201+b5534a1-1build2