[Zope] Timeout on server when python script is running

Hello everybody! I have a python script running from a plone site..it takes a lot of time (1 hour maybe more) but I need to run it just for data recovery if something goes wrong. after about 20 minutes a "Timeout on server" message pops up.. I tried and found where to change timeouts in zope.conf, but nothing changed. Wrong place? Please help, thanks! Stef