Comment 56 for bug 333386

Okay, I'm providing required data from WORKING, LIVE version of Ubuntu 8.10:
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uname -a:
  Linux ubuntu 2.6.27-4-generic #1 SMP Wed Sep 24 01:29:06 UTC 2008 x86_64 GNU/Linux
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cat /sys/devices/platform/acer-wmi/interface:
  WMID
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ls -la /proc/acpi/video:
  totale 0
  dr-xr-xr-x 3 root root 0 2009-06-10 15:29 .
  dr-xr-xr-x 11 root root 0 2009-06-10 15:22 ..
  dr-xr-xr-x 10 root root 0 2009-06-10 15:29 GFX0
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ls -la /sys/devices/platform/acer-wmi/backlight:
  ls: impossibile accedere a /sys/devices/platform/acer-wmi/backlight: Nessun file o dir..)
  (sorry, it's italian and it means "NO SUCH FILE OR DIRECTORY")
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ls -la /sys/devices/platform/acer-wmi/backlight/acer-wmi/:
  (same as previous directory, no such file or directory)
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Moreover, i found these files related to BRIGHTNESS (for complete list see attached log):
  /etc/acpi/thinkpad-brightness-down.sh
  /etc/acpi/thinkpad-brightness-up.sh
  /etc/acpi/video_brightnessdown.sh
  /etc/acpi/video_brightnessup.sh
  /etc/acpi/events/asus-brightness-down
  /etc/acpi/events/asus-brightness-up
  /etc/acpi/events/panasonic-brightness-down
  /etc/acpi/events/panasonic-brightness-up
  /etc/acpi/events/sony-brightness-down
  /etc/acpi/events/sony-brightness-up
  /etc/acpi/events/thinkpad-brightness-down
  /etc/acpi/events/thinkpad-brightness-up
  /etc/acpi/events/tosh-brightness-down
  /etc/acpi/events/tosh-brightness-up
  /etc/acpi/events/video_brightnessdown
  /etc/acpi/events/video_brightnessup
  /etc/acpi/resume.d/50-tosh-restore-brightness.sh
  /etc/acpi/suspend.d/50-tosh-save-brightness.sh
  /etc/laptop-mode/conf.d/lcd-brightness.conf
  /usr/lib/gnome-power-manager/gnome-brightness-applet
  /usr/lib/hal/scripts/hal-system-lcd-get-brightness
  /usr/lib/hal/scripts/hal-system-lcd-set-brightness
  /usr/lib/hal/scripts/linux/hal-system-lcd-get-brightness-linux
  /usr/lib/hal/scripts/linux/hal-system-lcd-set-brightness-linux
  /usr/share/laptop-mode-tools/modules/lcd-brightness

and for instance, inside video_brightnessdown.sh, you can see the following script:
  #!/bin/sh
  test -f /usr/share/acpi-support/key-constants || exit 0
  . /usr/share/acpi-support/key-constants
  acpi_fakekey $KEY_BRIGHTNESSDOWN

but if I execute this script it doesn't do anything. I dunno what BRIGHT-FN keys are mapped to, but they DO work in this kernel.