I noticed the DNS tests on certification (even for Sage) don't check to see if all the DNS servers support IPv6 or not.
It seems enough to delegate the subdomain you are using for the tests to an IPv6 enabled server (such as the ones provided by HE)
Great but then one still needs IPv4 to query the parent server for the NS records pointing to that sub domain :-\
P.s waiting for IPv6 support from my providers then the Nameservers for the whole domain will be ipv6'd ;-)
QuoteGreat but then one still needs IPv4 to query the parent server for the NS records pointing to that sub domain
Not universally true.
Percentage of TLDs with IPv6 nameservers: 83.6%
Source: http://bgp.he.net/ipv6-progress-report.cgi
So, for every 5 out of 6 TLDs, your statement is false.
For the sage test I used ip6.mydomain.com.
However mydomain.com is on nameservers that aren't yet IPv6 enabled.
What I did is add NS entries in MY nameservers for ip6.mydomain.com pointing at the HE.net servers.
so in order to lookup host.ip6.mydomain.com you're going to have to first Hit my Nameservers to find the NS record pointing to ip6.mydomain.com
Your zone's name servers are your choice. Therefore, I don't see a problem (other than one you caused yourself).