Deadman.org: Configuring the Intellimouse Explorer in XFree86 V4+

“After many many hours of restarting X, we’ve found that, in
order to get all seven of the buttons to be visible to X, you need
to define the mouse as follows:”

 Section "InputDevice"
         Identifier "Mouse0"
         Driver "mouse"
         Option "Protocol" "ExplorerPS/2"
         Option "Device" "/dev/mouse"
         Option "Buttons" "7"
         Option "ZAxisMapping" "6 7"
 EndSection

Complete
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