The July 2007 TechNet Cable Guy article in TechNet magazine, "IPv6 Traffic over VPN Connections," describes how IPv6 traffic can be sent over virtual private network (VPN) connections that are established across the IPv4 and IPv6 Internets using Windows Vista, Windows Server 2008 (now in beta testing), Windows XP, and Windows Server 2003.
For additional resources about VPNs in Windows, see:

For a list of previous The Cable Guy articles, see
For the current issue of TechNet Magazine, see