Comment 38 for bug 573984

Well the problem seems to be with the BIOS so the solution varies greatly between laptop models, unfortunately. But WorkspaceSwitcherApplet, WindowListApplet and ShowDesktopApplet don't seem connected to acpi at all (just looking at their names, I assume they have something to do with Alt+Tab, switching between workspaces and such), it's strange that they should fail. What did you do exactly?