We do not support it for the moment, as we use HTTPS to connect to our system, and WebDAV over HTTPS over Windows OS for example, works only if a computer has updated-version files or has the latest installed build. or you may face an error message from Windows O.S. "The folder you entered does not appear to be valid. Please choose another" at the moment you are trying to add a network resource.
Another issue in Windows Vista includes only the WebDAV redirector. So if you tried to install MS-Office, or OLE-DB, or IE, or "Microsoft Update for Web Folders" you will get the original "Web folders" client.
And the update can work only at the 32bit of Windows Vista ( or even Windows XP ), And Microsoft report that 64 bit versions of Windows will never support the "Web folders" client. So users limited to use WebDAV via the native Web Client service redirector.
And for Mac users for example, the WebDav is only supported using HTTPS only with Mac OS X 10.4 (Tiger) and not before that.
As you can see, there are a lot of issues when using WebDav with HTTPS, so for many issues, the WebDav is not yet included in DSS.