Comment 8 for bug 802197

Only if to make sure that everybody has a workaround for the time the fix that addresses the real problem is published and distributed:
A temporary workaround that users affected by this bug could apply would be

- Open a terminal and type
sudo gedit /etc/fstab
- Now a editor window opens. Add the following line to the end of the text this window contains:
sys /sys sysfs
- Save and close the editor.
- Done
After a reboot the sys filesystem is mounted by a different mechanism that during mounting it automatically adds the information about this to /etc/mtab.