he - net - ipv6 - "professional" what fun !

just had to wait for the subnet delegation of authority to propagate to validation checking program area -  some things still take time to finally work.

this part is setting up "reverse dns" (given an IP address, look up the FQDN, fully qualified domain name), but part of that process requires steps that are not instantaneous --

check out ipv6.he.net and click on "certifications"

among the various "test levels" for certification in HE's program -- 

 Newbie Test  ; Score: 5 / 5

This is a basic level test of the informationhere. With this primer at hand these questions should be a snap for you.

 Explorer Test  ; Score: 1 / 1

This test validates that you have Native or Tunneled IPv6.

 Enthusiast Test  ; Score: 1 / 1

This test validates that you have an IPv6 capable machine setup that can browse the web via IPv6, as well as the fact that you have a web server setup that can serve files via IPv6.

 Administrator Test  ; Score: 1 / 1

This test validates that your SMTP server is able to accept mail over IPv6

 Professional Test  ; Score: 1 / 1

This test validates that Reverse DNS for the IPv6 address of your SMTP server is properly configured.