fglrx (not installed): fglrx kernel module failed to build

[fhein]

Trying to install Catalyst 12.6 from ATI homepage, because the one in Ubuntu repo doesn't seem to work. I get the following problem:

more /var/lib/dkms/fglrx/8.970/build/make.log
DKMS make.log for fglrx-8.970 for kernel 3.5.0-17-generic (x86_64)
Sun Nov 4 10:47:34 CET 2012
AMD kernel module generator version 2.1
doing Makefile based build for kernel 2.6.x and higher
rm -rf *.c *.h *.o *.ko *.a .??* *.symvers
make -C /lib/modules/3.5.0-17-generic/build SUBDIRS=/var/lib/dkms/fglrx/8.970/bu
ild/2.6.x modules
make[1]: Entering directory `/usr/src/linux-headers-3.5.0-17-generic'
  CC [M] /var/lib/dkms/fglrx/8.970/build/2.6.x/firegl_public.o
/var/lib/dkms/fglrx/8.970/build/2.6.x/firegl_public.c: In function ‘KCL_MEM_Allo
cLinearAddrInterval’:
/var/lib/dkms/fglrx/8.970/build/2.6.x/firegl_public.c:2152:5: error: implicit de
claration of function ‘do_mmap’ [-Werror=implicit-function-declaration]
/var/lib/dkms/fglrx/8.970/build/2.6.x/firegl_public.c:2152:13: warning: cast to
pointer from integer of different size [-Wint-to-pointer-cast]
cc1: some warnings being treated as errors
make[2]: *** [/var/lib/dkms/fglrx/8.970/build/2.6.x/firegl_public.o] Error 1
make[1]: *** [_module_/var/lib/dkms/fglrx/8.970/build/2.6.x] Error 2
make[1]: Leaving directory `/usr/src/linux-headers-3.5.0-17-generic'
make: *** [kmod_build] Error 2
build failed with return value 2

ProblemType: Package
DistroRelease: Ubuntu 12.10
Package: fglrx 2:8.970-0ubuntu1
ProcVersionSignature: Ubuntu 3.5.0-17.28-generic 3.5.5
Uname: Linux 3.5.0-17-generic x86_64
ApportVersion: 2.6.1-0ubuntu6
Architecture: amd64
CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins'
CompositorRunning: None
DKMSKernelVersion: 3.5.0-17-generic
Date: Sun Nov 4 10:47:38 2012
DistUpgraded: 2012-11-03 23:10:19,320 DEBUG enabling apt cron job
DistroCodename: quantal
DistroVariant: ubuntu
DkmsStatus: fglrx, 8.970: added
GraphicsCard:
 Advanced Micro Devices [AMD] nee ATI RV770 [Radeon HD 4850] [1002:9442] (prog-if 00 [VGA controller])
   Subsystem: Advanced Micro Devices [AMD] nee ATI MSI R4850-T2D512 [1002:0502]
InstallationDate: Installed on 2011-10-15 (385 days ago)
InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Release amd64 (20111012)
MachineType: Gigabyte Technology Co., Ltd. EP45-DS4
MarkForUpload: True
PackageVersion: (not installed)
ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-3.5.0-17-generic root=UUID=ec8b2963-1343-4b74-9351-f697d7aa9b62 ro quiet splash vt.handoff=7
SourcePackage: fglrx-installer
Title: fglrx (not installed): fglrx kernel module failed to build
UnitySupportTest:
 Error: command ['/usr/lib/nux/unity_support_test', '-p', '-f'] failed with exit code 1: X Error of failed request: BadRequest (invalid request code or no such operation)
   Major opcode of failed request: 153 (GLX)
   Minor opcode of failed request: 19 (X_GLXQueryServerString)
   Serial number of failed request: 22
   Current serial number in output stream: 22
UpgradeStatus: Upgraded to quantal on 2012-11-03 (0 days ago)
dmi.bios.date: 07/11/2008
dmi.bios.vendor: Award Software International, Inc.
dmi.bios.version: F8b
dmi.board.name: EP45-DS4
dmi.board.vendor: Gigabyte Technology Co., Ltd.
dmi.chassis.type: 3
dmi.chassis.vendor: Gigabyte Technology Co., Ltd.
dmi.modalias: dmi:bvnAwardSoftwareInternational,Inc.:bvrF8b:bd07/11/2008:svnGigabyteTechnologyCo.,Ltd.:pnEP45-DS4:pvr:rvnGigabyteTechnologyCo.,Ltd.:rnEP45-DS4:rvr:cvnGigabyteTechnologyCo.,Ltd.:ct3:cvr:
dmi.product.name: EP45-DS4
dmi.sys.vendor: Gigabyte Technology Co., Ltd.
version.compiz: compiz 1:0.9.8.4-0ubuntu3
version.ia32-libs: ia32-libs 20090808ubuntu36
version.libdrm2: libdrm2 2.4.39-0ubuntu1
version.libgl1-mesa-dri: libgl1-mesa-dri 9.0-0ubuntu1
version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
version.libgl1-mesa-glx: libgl1-mesa-glx 9.0-0ubuntu1
version.xserver-xorg-core: xserver-xorg-core 2:1.13.0-0ubuntu6
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.7.3-0ubuntu2
version.xserver-xorg-video-ati: xserver-xorg-video-ati N/A
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.20.9-0ubuntu2
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.2-0ubuntu3