How do I get my scrollwheel to work in Firefox/Mozilla in Xorg on Linux?

– Log on as root
– Edit file /etc/X11/xorg.conf with your favorite editor:

The MS Explorer 3.0 really has 7 buttons: left, right, middle, scroll up, scroll down and 2 thumb buttons, which X needs to know.
My section looks like this, which should work for you as well.

Section "InputDevice"
Identifier "Configured Mouse"
Driver "mouse"
Option "Device" "/dev/input/mice"
Option "ButtonMapping" "1 2 3 6 7 4 5"
Option "Buttons" "7"
Option "ZAxisMapping" "4 5"
EndSection

Please note that certain options might vary from distro to distro, such as the Device and Protocol options.

I use both Debian (unstable) and Ubuntu (5.10), on which this sections work perfectly.