[Zope] invalid id "items"

Hi! I would like to use boa constructor for zope (zope 2.9.4-final) debugging. In boa you can define a zope connection to inteact with the zope server. Starting a boa zope connection boa creates a zoa folder in the zope root containing a couple of objects. Apparently boa also tries to create an object with the id "items" but this fails. Zope tells me that "The id "items" is invalid - it is already in use.". I tried to find the already existing object with id "items" but without success. Please can anyone give me a hint where I can find this object or how I can solve this problem? Thank you very much. Jens