The zoom x7n is finally working for IPv6 on PPPoA. We have been sent new code which does this.
This is yet another low cost DSL router with working IPv6 - we have tested on our standard broadband service and it received a prefix delegation which was announced on the LAN and routed IPv6 traffic. Logs show some slight quirks, but nothing major. Basically, it is working.
Hopefully this will be released as their standard code shortly.