Comment 12 for bug 133569

If you look at the openssh log message provided above, you'll see the IP of the
offending host, and so there is sufficient information - denyhosts blocks by IP
rather than hostname. So, I believe denyhosts should block that host, and this
is a fairly severe bug.

Looking a bit harder into it, I think (as suggested by your mail to the
user-list) that in file /usr/lib/python2.4/site-packages/DenyHosts/regex.py

FAILED_ENTRY_REGEX7 = re.compile(r"""User (?P<user>.*) not allowed because not
listed in AllowUsers""")

should be replaced with

FAILED_ENTRY_REGEX7 = re.compile(r"""User (?P<user>.*) .*from
(::ffff:)?(?P<host>\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}) not allowed because not
listed in AllowUsers""")

I'll test this locally, but that seems to be the crux of it - REGEX7 contains no
pattern to match the host.