[Zope] RDFSummary problem

Hi all, I'm using Eionet's RDFSummary. I have Zope 2.6 on win2kpro, and my lan has a MS proxy server with authentication. If I start Zope with the start.bat I can connect, for example, to this page: http://www.polare.com/news/HPE/xml/feeds/86/186.xml, but if I start Zope as service, when I try to connect to the same RSS url, I have this error: Error Type: URLError URLError: <urlopen error (10061, 'Connection refused')> Can anyone explain this? Thanks, Michele