[Zope-CMF] folder_factories and add permissions

[Jens-E. Hansen]

Hi!

I would like to achieve that a Member can add only selected portal types in a 
PortalContentFolder.

What I have done so far:

I created a new PortalContentFolder based portal type and filtered the allowed types 
which can be added. The workflow for this portal type sets the permissions on creation time to
"Acquire permissions settings" except for the permissions "Add portal collector". Only the owner is allowed
to add a collector. Now if a Member calls the folder_factory in this folder he can still add a collector.

If the workflow sets "Add portal content" permissions only for the owner and not for the Member the
Member can't add any portal content except for portal folders and portal topics.

Can someone please give me a hint?

Thank you
Jens-E.