[Zope] Portable way to get to OFS/dtml

Simple question for Python Product developers: Want to make sure that a properties management view in my product can't have properties added, only edited. Looked in OFS/PropertyManager.py and found the reference to property_extensible_schema__. Added to my product: manage_propertiesForm=DTMLFile('../../OFS/dtml/properties', globals(), property_extensible_schema__=0) Which works fine. Question is: what's the best way to handle getting to OFS/dtml rather than this ugly ugly breakable hack. Thanks! -- Joel BURTON | joel@joelburton.com | joelburton.com | aim: wjoelburton Independent Knowledge Management Consultant