I've done the very minimum amount of work required to get Cacheboy-1.6.PRE2 to the point where it'll handle IPv6 client requests. I've put it in front of http://www.cacheboy.net/ which now has v4 and v6 records.
There's still plenty of work to do to bring it up to par with the Squid-3 IPv6 support but that will have to wait a while. Specifically, (if anyone feels up to handling it), the dns, ipcache and fqdncache code all needs to be massaged to support IPv4 and IPv6 handling. It shouldn't be that much work.
Cacheboy-1.6 is definitely now in the "freeze and fix bugs as they creep up" stage. I'll continue the memory allocator and HTTP parser code reimplementation in their respective branches and get them ready for merge once I'm happy 1.6 is stable. The rest of the IPv6 support will also have to wait.