The Storage Team Blog about file services and storage features in Windows and Windows Server.
DFS Namespaces or DFSN management command line tools are available on Windows Server 2008 and also on Windows Vista SP1 as part of the Microsoft Remote Server Administration Tools (RSAT). The three available tools are Dfsutil.exe, Dfscmd.exe and Dfsdiag.exe.
To install DFSUtil, DFSDiag and DFScmd on Vista, download the Remote Server Administration Tools for Windows Vista Service Pack 1.
Will it work from XP SP3 as well? or just vista?
You can download it for Windows XP from here: