make multimedia keys and scroll buttons of an acer 5920g work in ubuntu 8.04 hardy heron

Roughly,
backup your xorg.conf
sudo cp /etc/X11/xorg.conf /etc/X11/xorg.conf.original

edit the xorg.conf
sudo gedit /etc/X11/xorg.conf

to the following

# xorg.conf (X.Org X Window System server configuration file)
#
# This file was generated by dexconf, the Debian X Configuration tool, using
# values from the debconf database.
#
# Edit this file with caution, and see the xorg.conf manual page.
# (Type "man xorg.conf" at the shell prompt.)
#
# This file is automatically updated on xserver-xorg package upgrades *only*
# if it has not been modified since the last upgrade of the xserver-xorg
# package.
#
# If you have edited this file but would like it to be automatically updated
# again, run the following command:
# sudo dpkg-reconfigure -phigh xserver-xorg

Section "InputDevice"
Identifier "Generic Keyboard"
Driver "kbd"
Option "XkbRules" "xorg"
Option "XkbModel" "pc105"
Option "XkbLayout" "us"
EndSection

Section "InputDevice"
Identifier "Configured Mouse"
Driver "mouse"
# Option "CorePointer"
Option "SendCoreEvents" "true"
EndSection

#Section "InputDevice"
# Identifier "Synaptics Touchpad"
# Driver "synaptics"
# Option "SendCoreEvents" "true"
# Option "Device" "/dev/psaux"
# Option "Protocol" "auto-dev"
# Option "HorizEdgeScroll" "0"
#EndSection

Section "InputDevice"
Identifier "TouchPad"
Driver "synaptics"
Option "CorePointer"
Option "Protocol" "event"
Option "Device" "/dev/input/eventtouchpad"
Option "MaxTapTime" "100"
Option "MaxTapMove" "220"
Option "AccelFactor" "0.05"
Option "SHMConfig" "true"
EndSection

Section "InputDevice"
Identifier "AcerMediaKeys"
Driver "evdev"
Option "Device" "/dev/input/eventkeys"
Option "SendCoreEvents" "true"
EndSection

Section "Device"
Identifier "Configured Video Device"
Driver "nvidia"
Option "NoLogo" "True"
EndSection

Section "Monitor"
Identifier "Configured Monitor"
EndSection

Section "Screen"
Identifier "Default Screen"
Monitor "Configured Monitor"
Device "Configured Video Device"
Defaultdepth 24
EndSection

Section "ServerLayout"
Identifier "Default Layout"
screen "Default Screen"
# Inputdevice "Synaptics Touchpad"
Inputdevice "TouchPad"
Inputdevice "AcerMediaKeys"
Inputdevice "Configured Mouse"
EndSection

Section "Module"
Load "glx"
EndSection
###########################################


Now do the following:
sudo gedit /etc/udev/rules.d/10-acersynaptics.rules

and paste the following:
SUBSYSTEMS=="input", ATTRS{phys}=="isa0060/serio4/input0", KERNEL=="event*", NAME="input/eventtouchpad"
SUBSYSTEMS=="input", ATTRS{phys}=="isa0060/serio3/input0", KERNEL=="event*", NAME="input/eventkeys"


Save and exit. I think this should be enough for the scroll buttons.

For the multimedia keys now to work.
Install xbindkeys
sudo apt-get install xbindkeys

Make them run at startup. The simplest is go to System->Preferences->Session

On your home directory
gedit ~/.xbindkeysrc

and paste the following (this is for exaile).
"exaile -t"
b:17

"exaile -s"
b:18

"exaile -p"
b:19

"exaile -n"
b:20


Restart and it should now be working.
I think that's all. There is also a post in the ubuntuforums from which I got the info.