The certificate for (ftp|www|bugs).g10code.com expired on 2011-12-23.

Also, oddly, while I can convince Firefox to allow the old cert for (ftp|www),
it refuses with a different error message ("uses an invalid security
certificate.") with no option to override. This is only a guess, but perhaps
the difference is that ftp and www are CNAMEs for kerckhoffs, while bugs is an
extra A record, for which the corresponding PTR does not match.