Same problem here on Vaio VGN-SR after update to Lucid Lynx.
Brightness does not change with Fn keys and Power management properties.
When doing "sudo echo 52 > /proc/acpi/video/VGA/LCD/brightness" I've got a permission denied error with "ls -al" giving
-rw-r--r-- 1 root root 0 2010-04-30 20:27 brightness
Only when doing "sudo chmod 646 /proc/acpi/video/VGA/LCD/brightness" changing brightness is possible on command line.
But Fn keys and Power management properties are still not changing anything.
Same problem here on Vaio VGN-SR after update to Lucid Lynx.
Brightness does not change with Fn keys and Power management properties.
When doing "sudo echo 52 > /proc/acpi/ video/VGA/ LCD/brightness" I've got a permission denied error with "ls -al" giving video/VGA/ LCD/brightness" changing brightness is possible on command line.
-rw-r--r-- 1 root root 0 2010-04-30 20:27 brightness
Only when doing "sudo chmod 646 /proc/acpi/
But Fn keys and Power management properties are still not changing anything.
I don't know if it's connected, I hope it helps.