Hi,
I have installed ubuntu 12.04 in my Apple workstation. I also installed the gnome-3 apart from default unity desktop environment.
It was working fine, but recently its mouse and keyboard stopped responding. Only mouse cursor is there but not moving.
I tried following till now..
1. removed .Xautohrity and reboot, but no solution.
2. reconfigured lightdm, problem not solved.
3. tried to login in recovery mode.. but again fail to proceed as
mouse and keyboard not responding.
4. changed /etc/linghtdm/lightdm.conf for auto login. now I can directly enter to my user account but mouse and keyboard still not responding.

Please look in this issue as I am struck.