IPv6 for machines behind NAT

[Pongthep Kulkrisada <ptkrisada%gmail.com@localhost>]

Hi All,

I have asked this problem somewhere in this list but focusing something else.
So I should open a new thread asking specifically.
Sorry for redundancy.

I'm running 5.1_STABLE and 6.0_RC2 on i386 from behind NAT.
Is it possible to get IPv6 for NetBSD behind NAT?
I did much googling and tried installing these apps, but they all do not work.
Here are details.

net/tspc - On NetBSD, only /dev/gif0 is capable to carry IPv6 packets for 
direct internet connection. UDP encapsulation is normally carried over 
/dev/tun0 through NAT gateway. But I tried configuring tun0 interface in 
/usr/pkg/etc/tspc.conf. It still doesn't work as NetBSD does not support UDP 
encapsulation.

net/hp6to4 - It requires direct connection to the internet. It only does 
mapping IPv4 to IPv6. It's not for machines behind NAT, whose IP is masqueraded.

net/miredo (teredo) - It is designed for machines behind NAT to get IPv6 on 
NetBSD. But I have tried it many times. It still doesn't work. AFAIK it was 
known to run on NetBSD-4 only.

Are there any workaround?
Any suggestions would be very highly appreciated.

Thanks,

-- 
Pongthep Kulkrisada
 
"UNIX is basically a simple operating system,
but you have to be a genius to understand the simplicity."
-- Dennis M. Ritchie