[Zope] Defining my own security

[Steve Jibson]

Okay, here goes...

I have created a Zope Product that extends a Zope Folder object and I 
want to add a non-traditional security check before allowing users to 
"View" stuff in the "folder".  For reasons that are too complicated to 
explain here, I can't use Zope roles and permissions for this check (in 
fact, this check should be done in addition to Zope's existing security 
mechanism checks).  What I want to do is verify that a particular 
variable in the "Session" matches a specific property of the "folder". 
If it does not match, I want to raise an unauthorized error.

Is this kind of thing possible?  Any help will be appreciated.

Thanks,

Steve