As it's getting late - if not fixed & one what's nautilus-gksu to work then simply sudo cp /usr/lib/nautilus/extensions-2.0/libnautilus-gksu.so /usr/lib/nautilus/extensions-3.0/
As it's getting late - if not fixed & one what's nautilus-gksu to work then simply nautilus/ extensions- 2.0/libnautilus -gksu.so /usr/lib/ nautilus/ extensions- 3.0/
sudo cp /usr/lib/