Possible Duplicate:
How to make xinput settings persist after devices are unplugged, replugged, and after shutdown, restart, etc?
How can I run the terminal command sudo xinput set-button-map "Logitech Unifying Device. Wireless PID:101b" 1 10 3 4 5 6 7 8 9 2 at every startup?
This command affects the GUI, so it must be executed after the GUI is set up. If you can live without your custom mouse button assignment on the login screen, add the command to your startup applications. Don't use sudo, it isn't useful here (and in fact might not work).
With a Gnome interface, the startup applications are in "System > Preferences > Startup Applications". With the Unity interface, they are in "Applications > Other > Startup Applications". See Adding program to session startup in the Ubuntu community documentation for more details.
