Comment 7 for bug 136453

Nemanja, thank-you for testing that. At least in your case we seem to have ruled that Thinkpad-specific change out.

Up to now the descriptions of the problem had focused on the acpi-support update but I see khul has just reported that xserver-xorg-video-vesa was also updated - and that may have more impact on the errors you're seeing.

Could each of you having this problem please check which updates were applied just prior to you first noticing the problem?

You can do this from Synaptic Package Manager through its File > History dialog and stepping through the dates. Please report all updated packages, not just the two being talked about here, just-in-case others have a bearing on the issue.