Notes regarding the usage of WebDav
There is an untested hypothesis that RequireSignOrSeal may cause windows XP to fail to authenticate to a non ssl webdav server (please update if you prove either way) - AdrianKitto
Windows XP (Pro at least) appears to be able to connect to SSL dav servers by default. However, Basic HTTP authentication is disabled by default. Instructions for enabling Basic auth via a Registry edit can be found at http://support.microsoft.com/?kbid=841215
With this change made, XP will happily map an SSL+Basic share as served by Apache2+mod_dav.
The remaining issue I have is that Windows will not allow the user to execute applications on the share, open documents using the default action, or even open documents as writable from within local applications such as Word. You have to copy the doc to local storage, edit it, then copy it back, overwriting the old version. Haven't found a way around this policy, if it can be done at all. Anyone?