How to:IPv6 base client-server application at different subnet

Hi All,

I am creating a client-server application for Ipv6 protocol on Windows XP platform using C++.

I am able to communicate using IPv6 protocol if Client and server are in the same subnet but if Client and server are in different subnet , then communcation is getting fail.

Thanks

In above condition i am getting 10065 error while connect.
Same code is working fine in same subnet.
Please assist is there any other setting for different subnet.

Thanks