[Zope-dev] Anyone know how to add a property to a Zope Product (not its instances)?

[Craeg K. Strong]

I am developing a new Zope product in python.  Normally one adds 
properties to a product like so:

class newProduct(SimpleItem, etc):

    meta_type 'NewProduct'

    _properties = (
     {'id': 'title',     'type':'string'},
     { 'id':'description',    'type':'string'},
     {'id':'foobar' , 'type':'string'"},
    )

   . . .

This defines properties for instances of the new Product.   But I want 
to add properties for the product itself.
These properties would show up in the property sheet of the PRODUCT, not 
its instances-- ie in
Root Folder/Control_Panel/Products/NewProduct on the Properties tab.

By default, Zope adds the title and version properties, for which it 
gets the value from version.txt and meta_type,
but does anyone know a way to add more?

Thanks in advance,

--Craeg