[Zope] ZSyncer and Zope-2.8.0

Hi, I'm trying to use ZSyncer 0.6.1 to synchronise simple objects (page templates...) between a Zope-2.7.6 source database and a Zope-2.8.0 destination database (both on Solaris with Python 2.3.4). I'm using a user which have a "Manager" role on both sides, but I can't manage ZSyncer to work : an "Unauthorized" exception is always raised ! I can't even manage to see a listing of the different folders. Any help would be great !! Thanks, Thierry