$ /usr/sbin/exim -bh 127.0.0.1

**** SMTP testing session as if from host 127.0.0.1
**** but without any ident (RFC 1413) callback.
**** This is not for real!

>>> host in hosts_connection_nolog? no (option unset)
>>> host in host_lookup? yes (matched "*")
>>> looking up host name for 127.0.0.1
>>> IP address lookup yielded localhost
>>> gethostbyname2 looked up these IP addresses:
>>>   name=localhost address=::1
>>>   name=localhost address=127.0.0.1
>>> checking addresses for localhost
>>>   ::1
>>>   127.0.0.1 OK
>>> host in host_reject_connection? no (option unset)
>>> host in sender_unqualified_hosts? no (option unset)
>>> host in recipient_unqualified_hosts? no (option unset)
>>> host in helo_verify_hosts? no (option unset)
>>> host in helo_try_verify_hosts? no (option unset)
>>> host in helo_accept_junk_hosts? no (option unset)
220 wombat.example.com ESMTP Exim 4.72 Wed, 19 Sep 2012 13:09:23 +0000
EHLO localhost
>>> host in pipelining_advertise_hosts? yes (matched "*")
>>> host in auth_advertise_hosts? yes (matched "*")
>>> host in tls_advertise_hosts? yes (matched "*")
250-wombat.example.com Hello localhost [127.0.0.1]
250-SIZE 52428800
250-PIPELINING
250-STARTTLS
250 HELP
AUTH is broken
503 AUTH command used when not advertised

Why on earth does it say the host is in auth_advertise_hosts but not return AUTH in the EHLO response? Someone, please throw me a clue here.