Brightness control button not working in my ubuntu 11.04

[midhun]

I am using ubuntu 11.04 on lenovo ideapad z570 machine.. my brightness
control button (fn + up/down arrow) is not working...... please help
me.....





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Midhun M E-mail :
mid...@prl.res.in
Junior Research Fellow
midhu...@gmail.com
Geosciences Division Phone : +9179-26314270
Physical Research Laboratory
26314053
Ahmedabad - 380009 Mobile : +919662735356

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[David John]

I have the same issue with the z570 +ubuntu 11
Disabling acpi enables brightness control, but standby/suspend options
will not work after that
I have not found a good solution to this issue, despite searching
online forums in some detail
Lot of users have reported this issue from time to time