Just installed 11.10. My Synaptics PS/2 mouse was working before (11.04) but post upgrade it stopped working right after login.
I did two things to (seemingly) fix it.
(1) sudo apt-get install --reinstall xserver-xorg-input-synaptics (2) gconftool-2 --type bool --set /desktop/gnome/peripherals/touchpad/touchpad_enabled true
After one reboot it seems to be working post login.
Just installed 11.10. My Synaptics PS/2 mouse was working before (11.04) but post upgrade it stopped working right after login.
I did two things to (seemingly) fix it.
(1) sudo apt-get install --reinstall xserver- xorg-input- synaptics gnome/periphera ls/touchpad/ touchpad_ enabled true
(2) gconftool-2 --type bool --set /desktop/
After one reboot it seems to be working post login.