I have had both AIS Firewall and the Windows 7 Firewall running together on my computers for almost a year without any complications

Windows 7 Firewall

[b]Support for stateful firewall handling of IPv6 transition protocols[/b]

Windows 7 and Windows Server 2008 R2 include support for an IPv6 transition technology called IP over HTTPS (IPHTTPS). IPHTTPS is a tunneling protocol that embeds IPv6 packets inside an HTTPS datagram inside an IPv4 network packet. IPHTTPS allows IPv6 traffic to successfully traverse some IP proxies that do not support IPv6 or some of the other IPv6 transition technologies, such as Teredo and 6to4. For a Windows Firewall inbound or outbound rule, you can set the TCP port to IPHTTPS instead of a number to have Windows Firewall automatically recognize and handle the connection appropriately.

In addition, Windows 7 and Windows Server 2008 R2 include support for an IPv6 transition technology called Teredo. Teredo is a tunneling protocol that embeds IPv6 packets inside a User Datagram Protocol (UDP) datagram inside an IPv4 network packet. For a Windows Firewall inbound rule, you can set the UDP port to Edge Traversal instead of a specific port number to have Windows Firewall automatically recognize and handle the connection appropriately



http://technet.microsoft.com/en-us/library/cc755158(WS.10).aspx

also see here

http://forum.avast.com/index.php?topic=79218.0

More here

Summary of IPv6 Enhancements in Windows 7
[url=http://sourcedaddy.com/windows-7/summary-ipv6-enhancements-windows-7.html] http://sourcedaddy.com/windows-7/summary-ipv6-enhancements-windows-7.html[/url]