virtual desktops

[Rob Clack <rob@theclacks.org.uk>]

I'm running kde-2.2.2, installed for me by a friend.  I used to have 4 
virtual desktops, but somewhere down the line I did something and now I 
only have one.  So I go to KDE menus, Preferences, Look & Feel, Virtual 
Desktops, and change it to 4.  Sadly, next time I log in, I'm back to 
1.   I can also set it via the KDE menus Control Centre, but that 
setting is also lost when I log out.

Can anyone tell me how to set it to 4 permanently?

Thanks
Rob Clack