[Zope-dev] ZODB Mountpoint broken?

ZODB Mountpoint distributed with Plone 4.1.2 always seems to create OFS.Folder even if the container-class is specified. Also getting a "KeyError: item already present wih same id" due to _setObject and _setOb both being called. Am trying to mount a plone.app.folder.folder.ATFolder from a separate Data.fs using instructions in: http://plone.org/documentation/kb/mount-zeo-into-plonesite