xorg-server upgrade killed my mouse

I have just upgraded xorg-server to 1.7.3. My keyboard works but my mouse is completely dead. The current mouse driver (not upgraded) is xorg-xf86-input-mouse-1.5.0-1. I tried removing the mouse driver, rebuilding and reinstalling it. I also tried removing both the server and the mouse driver and reinstalling both. Both attempts failed to cure the problem. Revdep shows nothing suspicious. /etc/X11/xorg.conf is attached; it has not been altered in any way. Can anyone suggest a way to proceed?