After going around in circles with my registrar Gandi, I was finally able to get IPv6 glue for my domain set up, no thanks to them. I was able to register glue records with another registrar (thanks to Ardya) and I was then able to apply them to my domain (chaz6.com).
I would implore you to write or send an email to VeriSign (maintainer of com, net and edu) and ask that they consider requiring registrars to support the registration of IPv6 glue records. I had a response back saying that they have no plans to do so, but with enough support they might change their mind. VeriSign can be reached at email@example.com