[Zope] Folders inaccessible through FTP when added by home-grown product

Hi I have a home-made python product. One bit adds Folder objects to the new instance of my class holding default stuff, etc. But these folders are not accessible via FTP, I get the error: cd: Access failed: 550 No such directory. (/sites/beta.xx.com/style) The following works: - ttw editing of the Folder objects - FTP access to my class of objects, even nested ones - adding a folder ttw to an instance of my class - ftp access works Where can I start figuring this out? F.