[Zope] ZSyncer fails to do authenticate under Zope 2.11

I am getting 401 errors with ZSyncer-0.7.1 using a configuration which worked with Zope 2.9 and an earler version of the ZSyncer product. Both use Python 2.4. Has anyone seen this problem? Can you recommend a fix? Is the CVS version of ZSyncer on Sourceforge a better choice? --