* Add a new desktop user called guest
* Change the encrypted password for guest in /etc/passwd to:
* Log in as Guest with no password (just press return for password)
* Use the user session switcher to switch to your original account
* Use the user session switcher again to switch back to the Guest account
* Guest account session is locked and cannot be unlocked- pressing return for password is rejected.
At the moment, the only way to unlock the guest account is pretty drastic, such as restarting GDM, which logs out ALL desktop sessions and restarts X, clearly not a good solution.
Any help much appreciated, thanks.