Edit /etc/freenet6/tspc.conf: Make sure that the values assigned to userid and passwd are the ones that you got by mail from Freenet6. Also add the following options if you need a /48 prefix delegation:

host_type=router
prefixlen=48

and in our example we changed

if_tunnel=tunFN

Change is due to a remark from Dr. Peter Bieringer: (see: http://www.tldp.org/HOWTO/Linux+IPv6-HOWTO/configuring-ipv6to4-tunnels.html

[This is now deprecated because using the generic tunnel device sit0 doesn't let specify filtering per device.]

see: http://www.tldp.org/HOWTO/Linux+IPv6-HOWTO/configuring-ipv6to4-tunnels.html