Achtung! the right way of doing is ::ffff:<ipv4>, so newer stuff will use that.
Based on the last posting, we are doing it now with an olsr mesh between the translators.
Between this two posts, jow fixed all remaining issues, making the setstuff shellscripts obsolete. He also fixed a HNA6 issue in the olsrd-luci package. Thanks, great work, jow.
Easy setup now, one internet4 gateway, one access node to give internet to the attached ipv4 clients.
I tried to draw it: ipv4-throught-ipv6-mesh.
gate:
- wan port is dhcp, lan port is 172.23.1.1/24
- siit0 gets a dummy address: 169.254.42.42
- wl0 gets an ipv6 address, in this case the fdca:ffee:babe::1:1/64
- we do a ::ffff:ffff:0/96 route into siit0, so everything from 6mesh goes into translation.
- an HNA6 of ::ffff:ffff:0:0/96 announces the mapped 0.0.0.0/0 ipv4 space.
- MTU on WAN, LAN down to 1400, ipv6 headers are slighly larger.
access1 has
- 172.23.2.1/24 on its lan, fdca:ffee:babe::1:2 on wl0 and the usual dummy address on siit0.
- we do a ::ffff:ffff:172.13.2.0/120 to siit0, because in this case, only traffic directed to clients needs to go into translation.
- same route as HNA6 announcement to catch the traffic out of the mesh.
- Also, MTU on LAN reduced to 1400.
To reproduce the setup, you need 2 broadcom based OpenWrt boxes, as the siit kernel module has not been ported to kernel 2.6.
its based on OpenWrt 8.09RC1 plus some patches, which add siit, enable ipv6 forwarding and fix ipv6 static routes. plus a config file.
you can also use ready made firmwareimages. then, there is a config tarball and a uci-dump for gate and a tarball and dump for access1.
for building more accessnodes, you need to alter the lan ipaddress, the ipv6 route into siit0 and the HNA6.
and, as it is just a proof of concept, telnet is open, firewall is open and the wanport of access1 is configured for my local LAN, so i can access telnet and webif from my notebook.
configuration of olsr nameservice plugin to get proper DNS automagically is left as an exercise to the reader. 
for questions, you can also join #freifunk on IRCNet or write to the wlanware mailinglist.
i would be happy to hear about any success.
