IPv6 Only FreeBSD

I'm setting up a couple of FreeBSD jails in an IPv6-only world. I was a bit surprised to note that although pkg.freebsd.org has a AAAA in DNS it's impossible to reach the DNS server that gives the AAAA answer over IPv6!

Only if I use a resolver that are both on IPv6 and legacy IP will I be able to install packages.

What can I do to help?