Hey,
I'm on Mac OS X 10.6 Snow Leopard with the Cisco EPC2425 modem+router (my ISP insists on a combined one, and flashing with DD-WRT is a no no

).
I originally configured with these options:
ifconfig gif0 create
ifconfig gif0 tunnel MY.EXTERNAL.IPV4.ADDRESS 216.66.80.26
ifconfig gif0 inet6 2001:470:1f08:136b::2 2001:470:1f08:136b::1 prefixlen 128
route -n add -inet6 default 2001:470:1f08:136b::1
But got this error
bash-3.2# ping6 he.net
PING6(56=40+8+8 bytes) fe80::226:4aff:fe19:e8c%gif0 --> 2001:470:0:76::2
ping6: sendmsg: Can't assign requested address
ping6: wrote he.net 16 chars, ret=-1
Request timeout for icmp_seq=0
ping6: sendmsg: Can't assign requested address
ping6: wrote he.net 16 chars, ret=-1
I then decided to try using my internal DHCP server assigned IP with this line:
ifconfig gif0 tunnel 192.168.1.14 216.66.80.26
But got this slightly different error:
bash-3.2# ping6 he.net
PING6(56=40+8+8 bytes) fe80::226:4aff:fe19:e8c%gif0 --> 2001:470:0:76::2
Request timeout for icmp_seq=0
Request timeout for icmp_seq=1
Request timeout for icmp_seq=2
Anybody got any suggestions for me? I really like being slightly ahead in web technologies (let's lead by example

), so I'd love to set up an IPv6 tunnel.