It adds a bit of latency (and is definitely not the best solution in
theory), but finally allows dropping IPv6 NAT and it works within the
constraits my home network has to live in.
When having DNSSEC activated (as it is the case on sbruder.de), dnsmasq
interfering in queries for hosts on the LAN often causes problems.
This domain is specifically for the case of not having DNSSEC on it.