Hi all, I've created a Product Step which is a subclass of Folder. I want restrict what types of objects I can put in an object of type Step. The "Developer's guide" has this to say on the subject: "If you wish to control which types of objects can be contained by instances of your product you can set the meta_types class attribute. This attribute should be a tuple of meta_types." I naively interpreted this such that I could put this in my class: meta_types = ('Step', 'SURef',) But this gives me the errors: Error Type: AttributeError Error Value: has_key With the backtrace: File /usr/lib/zope/lib/python/OFS/ObjectManager.py, line 271, in filtered_meta_types (Object: Step) So I found a tip on the Web, saying I could do this: meta_types = ({'name':'Step', 'action':'manage_addStepForm'},) Now, this doesn't give me an error, but the effect is that I get one more Step as alternative on the drop-down menu "Select type to add..." *in addition* to all the alternatives. But I wanted to restrict the possibilities, not augment them. What am I doing wrong? TIA Jesper -- Jesper Holmberg |"But how can | jesper.holmberg@enst-bretagne.fr | one be warm | ENST Br, BP 832, 29285 Brest, FRANCE | alone?" |