[Zope] Authorisation problem

[Roché Compaan]

I created a form in Zope with which the user can easily update the product
list through a simple interface.  I mainly used the content manager as
guidance in this effort.  I run into an simple problem however.

Following is the piece in the "builder" script that clones an existing
folder

<dtml-with "manage_clone(MyFolderName,REQUEST['id'],REQUEST)">
  <dtml-comment>
  <dtml-call "manage_changeProperties(
      title=REQUEST['title'],
      Code=REQUEST['Code'],
      Material=REQUEST['Material'],)">
  </dtml-comment>
  <dtml-call "thumbnail.manage_upload(REQUEST['thumbnail'])">
</dtml-with>

<dtml-call
"RESPONSE.redirect(DestinationURL()+'manage_main@update_menu=1')">

When I view the "designer" and submit my changes from the Designer form i
get an authentication error.  Zope says that i am not authorized to
"manage_changeProperties".
I've checked my id's in my designer form and they match the id's used in the
builder script.  I am also logged in as a user with manager and owner roles
and have no problem to change properties of folders in Zope itself.

What could this be?

Help appreciated.

Roché Compaan