>> >Any ideas what I might be doing wrong here?
>> 	your "gif0" interface is not IFF_UP.  try "ifconfig gif0 up".
>Nope.
>bash-2.04# ifconfig gif0 up
>bash-2.04# ping6 www.kame.net
>PING6(56=40+8+8 bytes) 3ffe:b00:c18:1fff::4dd --> 3ffe:501:4819:2000:5054:ff:fed
>c:50d2
>ping6: sendmsg: Message too long
>ping6: wrote www.kame.net 16 chars, ret=-1

	it may be that you need to start everything from scratch (reboot
	preferable), because you may have path mtu discovery results staying
	in routing table.

	could you show me the result of:
	ifconfig -a
	netstat -rnl
	ndp -i gif0

>Hmm, should three actually be a /dev/gif0 or is it just a logical device?

	no.  network interfaces are not present in /dev.

itojun