Same behavior on Acer Extensa 5230E and Ubuntu karmic, i686. The backlight does not change at all when I press Fn+Up/Down. Under jaunty it worked without any problems.
Current system: Linux karin-pc 2.6.31-19-generic #56-Ubuntu SMP Thu Jan 28 01:26:53 UTC 2010 i686 GNU/Linux
Same behavior on Acer Extensa 5230E and Ubuntu karmic, i686. The backlight does not change at all when I press Fn+Up/Down. Under jaunty it worked without any problems.
Current system: Linux karin-pc 2.6.31-19-generic #56-Ubuntu SMP Thu Jan 28 01:26:53 UTC 2010 i686 GNU/Linux
Tell me if I shall provide more information.