[horde] Expiring Sessions - Time advice

[S. Petty]

I have multiple users that share the same computer, and getting them to 
actually click the Logout button is proving to be quite a chore.  Of 
course, what that results in is the next person using the PC to go right 
into the previous user's mailbox.

It appears that I can set the length of time until the session expires, 
via the session_set_cookie_params, but the admin interface cautions that 
there may be issues with it.

Does anyone use this parameter with anything other than the default 0 
setting, or perhaps is there a better way to insure that sessions aren't 
maintained longer than necessary?

Thanks!		Sean