Multiple HELOs Rejected

I just installed the SMTP module and tried sending a couple test messages. They all failed. I asked the postmaster of the mail server if he could check his logs to see why it failed. He said:

So that module isn't bothering to wait until I send my HELO before trying to continue, which directly violates RFC and causes me to drop the connection. Also, possibly on the same connection or possibly on other connections, it's rapid-firing multiple HELOs at me, which also would cause me to drop the connection.

m ari.YYYY.org [aaa.bbb.ccc.ddd] due to pre-greeting traffic after 5 seconds
Mar 20 00:15:23 prospero sfcmilter: multiple HELOs from ari.YYYY.org [198.
154.194.93] - ignoring 'ari.YYYY.org'

Debugging info from the smtp module.

SMTP -> FROM SERVER:
SMTP -> get_lines(): $data was ""
SMTP -> get_lines(): $str is "554 prospero.XXXX.org ESMTP not accepting
messages "
SMTP -> get_lines(): $data is "554 prospero.XXXX.org ESMTP not
accepting messages "
SMTP -> FROM SERVER: 554 prospero.XXXX.org ESMTP not accepting messages
SMTP -> ERROR: EHLO not accepted from server: 554 prospero.XXXX.org
ESMTP not accepting messages
SMTP -> get_lines(): $data was ""
SMTP -> get_lines(): $str is "250-prospero.XXXX.org Hello
ari.YYYY.org [198.154.194.93], pleased to meet you "
SMTP -> get_lines(): $data is "250-prospero.XXXX.org Hello
ari.YYYY.org [198.154.194.93], pleased to meet you "
SMTP -> get_lines(): $data was "250-prospero.XXXX.org Hello
ari.YYYY.org [198.154.194.93], pleased to meet you "
SMTP -> get_lines(): $str is "250 ENHANCEDSTATUSCODES "
SMTP -> get_lines(): $data is "250-prospero.XXXX.org Hello
ari.YYYY.org [198.154.194.93], pleased to meet you 250
ENHANCEDSTATUSCODES "
SMTP -> FROM SERVER: 250-prospero.XXXX.org Hello ari.YYYY.org
[198.154.194.93], pleased to meet you 250 ENHANCEDSTATUSCODES
SMTP -> get_lines(): $data was ""
SMTP -> get_lines(): $str is "250 prospero.XXXX.org Hello
ari.YYYY.org [198.154.194.93], pleased to meet you "
SMTP -> get_lines(): $data is "250 prospero.XXXX.org Hello
ari.YYYY.org [198.154.194.93], pleased to meet you "
SMTP -> FROM SERVER:250 prospero.XXXX.org Hello ari.YYYY.org
[198.154.194.93], pleased to meet you
SMTP -> ERROR: STARTTLS not accepted from server: 250 prospero.XXXX.org
Hello ari.YYYY.org [198.154.194.93], pleased to meet you
SMTP -> get_lines(): $data was ""
SMTP -> get_lines(): $str is "550 5.0.0 Command rejected "
SMTP -> get_lines(): $data is "550 5.0.0 Command rejected "
SMTP -> FROM SERVER:550 5.0.0 Command rejected
SMTP -> ERROR: RSET failed: 550 5.0.0 Command rejected
StartTLS not supported by server or could not initiate session.
Redirecting to https://ari.YYYY.org/admin/config/system/smtp.