Brightness levels set to lowest level when trying to wake up laptop after screen has turned off due to inactivity

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I have a Lenovo B570 laptop and whenever the screen turns off due to inactivity (set to 10 minutes in System Settings > Screen) upon trying to reawaken the device, by moving the mouse or pressing a keyboard button, the screen will reawaken but the brightness levels are always set at the very lowest possible.
The hardware brightness keys (fn + up/down) do not work in this situation (though they work fine everywhere else).

I can enter my password 'blind' and unlock the screen. The brightness levels still remain at the very lowest levels but now the hardware keys do work and I can readjust the levels.

This bug occurs everytime the screen is turned off due to inactivity. Locking the screen (Ctrl + Alt + L) and reawakening does not cause this behaviour (though if the screen is manually locked and left inactive until 10 minutes have elapsed, then the brightness will be set to the lowest levels). Suspending or hibernating the machine does not result in this behaviour and work fine.

Sorry if I've filed in the wrong place or provided the wrong infomation, I was told it may be a kernel problem and this was the correct package choice etc.

ProblemType: Bug
DistroRelease: Ubuntu 11.10
Package: linux-image-3.0.0-14-generic 3.0.0-14.23
ProcVersionSignature: Ubuntu 3.0.0-14.23-generic 3.0.9
Uname: Linux 3.0.0-14-generic x86_64
AlsaVersion: Advanced Linux Sound Architecture Driver Version 1.0.24.
ApportVersion: 1.23-0ubuntu4
Architecture: amd64
ArecordDevices:
 **** List of CAPTURE Hardware Devices ****
 card 0: PCH [HDA Intel PCH], device 0: ALC272 Analog [ALC272 Analog]
   Subdevices: 1/1
   Subdevice #0: subdevice #0
AudioDevicesInUse:
 USER PID ACCESS COMMAND
 /dev/snd/controlC0: coversnail 1668 F.... pulseaudio
CRDA: Error: [Errno 2] No such file or directory
Card0.Amixer.info:
 Card hw:0 'PCH'/'HDA Intel PCH at 0xd0600000 irq 43'
   Mixer name : 'Intel CougarPoint HDMI'
   Components : 'HDA:10ec0272,17aa6014,00100001 HDA:80862805,80860101,00100000'
   Controls : 21
   Simple ctrls : 11
Date: Wed Jan 11 10:19:01 2012
HibernationDevice: RESUME=UUID=4bf0dee5-a21c-4c42-92e0-4ffe428f6078
InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Release amd64 (20111012)
MachineType: LENOVO 1068EMG
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.0.0-14-generic root=UUID=86b1bc33-1581-4c99-afd1-5229bc581847 ro quiet splash i915.i915_enable_rc6=1 pcie_aspm=force vt.handoff=7
RelatedPackageVersions:
 linux-restricted-modules-3.0.0-14-generic N/A
 linux-backports-modules-3.0.0-14-generic N/A
 linux-firmware 1.60
SourcePackage: linux
StagingDrivers: rts5139 mei
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 07/11/2011
dmi.bios.vendor: LENOVO
dmi.bios.version: 44CN36WW
dmi.board.asset.tag: Base Board Asset Tag
dmi.board.name: Emerald Lake
dmi.board.vendor: LENOVO
dmi.board.version: FAB1
dmi.chassis.asset.tag: Asset Tag
dmi.chassis.type: 10
dmi.chassis.vendor: LENOVO
dmi.chassis.version: 0.1
dmi.modalias: dmi:bvnLENOVO:bvr44CN36WW:bd07/11/2011:svnLENOVO:pn1068EMG:pvrLenovoB570:rvnLENOVO:rnEmeraldLake:rvrFAB1:cvnLENOVO:ct10:cvr0.1:
dmi.product.name: 1068EMG
dmi.product.version: Lenovo B570
dmi.sys.vendor: LENOVO

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I didn't notice it while searching initially but this could be a possible duplicate of: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/872652