IPv6 reverse lookup - lame delegation?

  if i try to log into my machines back in tokyo by IPv6 SSH, it takes
  very long time. i guess i found the reason - (possible) lame delegation
  of blah.ip6.int. ip6.arpa. query returns instantly.
  how could we fix it?

  the ip6.int entry times out, no servers reached.
  the ip6.arpa entry fails immediately w/ NXDOMAIN.

  the delegation for 3ffe:37:: is

7.3.e.f.f.3.ip6.int. in ns gemini.psc.edu.
                     in ns charon.psc.edu.


  these servers are -NOT- responding to queries.
  perhaps you should contact Michael Lambert for more detail.