No, our products do not support this older standard.
XMetaL Author Enterprise, XMetaL Author Essential and XMAX do support WebDAV (which I believe provides a similar level of file management support, essentially limited to file locking). XMetaL Author Enterprise only supports WebDAV when you are working with documents
other than DITA.
I've posted more general information about CMS connectivity here:
http://forums.xmetal.com/index.php?topic=262