[Zope] IIS, PCGI, authentication

I am running Zope under IIS using PCGI and it works great, but I can't view pages that require authentication. I found the following in the archive but it caused a forbidden error rather than popping up the login dialog. Does anyone know what the easiest way to do this is? T. Note that you probably have to tweak your IIS configuration to get IIS to pass authentication headers to Zope. You need to make sure that BOTH "Windows NT Challenge/Response" AND "Basic Authentication" are DESELECTED for the cgi directory where you placed the cgi exe. Otherwise, IIS will intervene on every request and try to do the authentication itself (which will fail, of course).