When I'm building a class which inherits from the OFS.Folder.Folder, how do I exlude the meta_types it brings with it (if it's there they come from). In other words, if I have a class, with meta_type 'MessageFilterFolder', which should only be able to contain instances of meta_type 'MessageFilter', what do I do (i.e. exlude all the other meta_types)? Thanks in advance. -Morten