is somewhere a tutorial how to setup ipv6 NAT router? or can you post how to do this? im using slack 10 for my router(configured with ipv6, btexact), my subnet host are win users. So what add to my configuration in linuxbox, and then how to setup win users pcs?

Don't think it is possible...

The Netfilter FAQ says that ip6tables doesn't do NAT yet...
Not sure if there is a workaround.

I thought one of the points of IPv6 was to make NAT obsolete, because everyone gets so many million unique IP addresses anyway?

Good point!

How does one go about getting an IPv6 address anyway?

em, so how to setup my subnet computers, to work with ipv6?
my net is:
--------------ROUTER: -------------
---------------------
ifconfig sit0 up \
&& ifconfig sit0 inet6 tunnel ::213.121.24.85 \
&& ifconfig sit1 inet6 add 2001:618:400::54f::1/128 \
&& route -A inet6 add ::/0 gw fe80::d579:1855 dev sit1 \
&& route -A inet6 add 2000::/3 gw fe80::d579:1855 dev sit1 \
&& ifconfig eth0 up \
&& ifconfig eth0 inet6 add 2001:618:400:ddef::/64 \
&& echo 1 > /proc/sys/net/ipv6/conf/all/forwarding \
&& echo 'interface eth0
{
AdvSendAdvert on;
prefix 2001:618:400:ddef::/64
{
AdvOnLink on;
AdvAutonomous on;
};
};' > /etc/radvd.conf \
&& /usr/bin/radvd start
---------------------
also there is an eth1 card, for ipv4 NAT
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how setup my hosts using this information? is this possible?