[Zope] Access Permission by Domain and without Login?

[Passin, Tom]

For a Zope 2.7/Plone 2 site, I would like to restrict (otherwise)
anonymous access to certain specific pages or methods to people making
the request from specific domains.  I know that I can specify a domain
for a particular user, but I want this to apply to anyone, without any
special per-user configuration, and without requiring a login.

Also I want to do this without putting Zope behind Apache or any other
proxy, if this is possible.  

I don't recall seeing this discussed.  Does anyone have suggestions as
to how to accomplish this?

Cheers,

Tom P