[Zope] Users who are allowed to work only within sessions?

[Itai Tavor]

I am building a site in which different people are responsible for editing
and adding documents at different folders. The site's client wants to
preview all changes before they go live. The editors can't be trusted not
to mess things up, so they can't be allowed to work on the actual site.

So, what I need is a way to allow certain users to work only inside a
session - which seems to be impossible, because the only way to get into a
session is to first log in, and then to activate the session. If an editor
fails to activate a session, they're free to mess up the site.

Can anyone think of a way to achieve this? Or is it already possible and I
can't see it?
--
Itai Tavor                      -- "Je sautille, donc je suis."    --
itavor@vic.bigpond.net.au       --               - Kermit the Frog --
-- 'Supposing a tree fell down, Pooh, when we were underneath it?' --
-- 'Supposing it didn't,' said Pooh after careful thought.         --