[Zope] Error on Tutorial

Zope 2.6.1 run on Solaris 8 with Python 2.2. Test and Manage Ok. When I try to install the tutorial, Zope send this error : Error Type: Bad Request Error Value: The ZGadflyDA product must be installed! The ZGadflyDA product is in the list under Product Management at /Control_Panel/Products On my PC it work's fine What's wrong? Francis