IPv6 over PPTP VPN from Windows XP - Traffic leaves without GRE

[cuthbei]

Hi,

I'm in the process of moving my tunnel from my home router to use PPTP VPN from XP, so I can use it whilst I travel. The PPTP VPN comes up fine with IPv4 and I can I that all my outbound traffic leaves my machine using this tunnel.

When I add an IPv6 global address and route to my machine using

ipv6 rtu ::/0 2/::216.66.80.26 pub
ipv6 adu 2/2001:470:xxxx:9a7::2

and trace on my machine I can see that traffic leaves my machine as IPv6 in IPv4 (without GRE/PPTP - proto 41) and returns via the PPTP tunnel (IPv6 in IPv4 in GRE in IPv4). This means no IPv6 communication. Can anyone guide me on how to force my XP machine to route packets outbound via the GRE/PPTP tunnel? The DST address of the IPv4 packet outbound is 216.66.80.26 (which makes sense, as this is the tunnel endpoint), but this IP has a specific route entry in my route table which avoids PPTP.

Network Destination        Netmask          Gateway       Interface  Metric
     216.66.80.26  255.255.255.255    192.168.202.1  192.168.202.131      10

Thanks, Cuthbei