[Zope] Problems with Ms-webfolders, iis, and pcgi

I am trying to gain access to Zope via webdav with the MS-webfolder client. This seems to work fine when I connect to Zope directly. However I also run zope behind iis using pcgi. When I do this I get an error saying there was a problem (but not details of what that problem was. If I use DAV explorer then I can see it behind IIS just fine. From the logs I suspect that webfolders is getting properties on the pcgi script or it's folder from IIS and denying me based on that rather than looking at the full url. Anyone know a way around all this? A related question is, anyone know how to make MS-frontpage play nice with Zope webdav?