Using "ExplorerPS/2" is good, but there is a better solution and works with all mice and all buttons.
You can use the Event Interface Driver.
I include a sample config:
Section "InputDevice"
Identifier "Mouse[0]"
Driver "mouse"
Option "Protocol" "evdev"
Option "Dev Name" "Logitech MX700" # cat /proc/bus/input/devices
Option "Dev Phys" "isa0060/serio1/input0" # cat /proc/bus/input/devices
Option "Device" "/dev/input/mice"
Option "Buttons" "10"
Option "ZAxisMapping" "9 10"
Option "Resolution" "800"
EndSection
(10 buttons for MX700,12 for MX1000, etc)
Then the usual changes for xmodmap. e.g "1 2 3 9 10 4 5 6 7 8"
You can see if the buttons work by running "xev" in a xterm.
There is a very good article
http://www.linux-gamers.net/modules/...p?articleid=46 that mentions many things
The old version of it was more thorough. I don't why some things are missing from the new one.
P.S the X Server shipped with slackware doesn't have EVDEV support so it will crash if you change the config.
Install the support first. visit the url i mention.