[Zope] Problem with Product example in 2.7 manual

[Jeff Gentry]

Hello ...

I've been following the Product creation example in the 2.7 Zope manual
(at http://www.plope.com/Books/2_7Edition/CustomZopeObjects.stx).  The
very first portion has one create a trivial product which can be selected
to add via 'Hello' and thus call the 'hello' method from earlier in the
example.  However, when I go to add this product, I get the login dialog
constantly (yet I am already logged in) and if I hit 'cancel' to avoid it
get the error:

Error Type: Unauthorized
Error Value: You are not allowed to access 'title_or_id' in this context

Note that I have a stock/brand new zope instance that I'm working on and
have not edited the permissions from the defaults in any way.  Is there
some permission change that I need to make for this to work?

Thanks
-J