fast user switching

[nicola .:kOoLiNuS:. losito]

Hi list,
on this box i'm writing from i'd like to have this kind of feature:

- have an X session at work, with evolution, gaim, xchat and other
programs running;
- when i'm goig away i'd like to lock the session;

BUT + AND

- i want that my father can log in a X session and check his email, or
browse the internet and then log off 
- when i come back i'll just have to re.insert my password and have my
desktop back.

With SUSE 10.0 all this worked without me having to configure anything.
Also the gnome-screensaver had an option to "log in as another user".

How do I achieve that on Fedora 5 {or CentOS/RHEL} ???
thanks

-- 
nicola .:kOoLiNuS:. losito 
http://koolinus.wordpress.com     http://www.koolinus.net

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