I believe this problem comes back on 12.04 because /dev/shm is now a link to /run/shm and when mount --bind of /dev/ is done the installer should also mount /run/shm
I believe this problem comes back on 12.04 because /dev/shm is now a link to /run/shm and when mount --bind of /dev/ is done the installer should also mount /run/shm