DNS issues with notmuchmail.org

[Justus Winter]

Hi,

I'm experiencing a weird issue, the dns servers provided by my isp
(once HanseNet, a local isp in Hamburg, Germany, then Alice, o2, not
sure who owns them now) do not return the record for notmuchmail.org:

% dig +short notmuchmail.org @213.191.74.12
% dig +short notmuchmail.org @213.191.92.82
% dig +short notmuchmail.org @4.2.2.4
74.208.220.233

You can verify the problem, their servers seem to be happy to talk to
anyone, not just their customers. Not sure if other domains are
affected, I just noticed this one b/c mails to the list were bouncing.

Any thoughts?
Justus