code expects 334, smtp server only sends 250. What does this mean?

Please see more info below (this is by setting PHPMailer's smtp's debug to true (line smtp.module:536)):

SMTP -> get_lines(): $data was ""
SMTP -> get_lines(): $str is "220 hostname ESMTP hostname; Sat Feb 9 12:02:13 2008
"
SMTP -> get_lines(): $data is "220 hostname ESMTP hostname; Sat Feb 9 12:02:13 2008
"
SMTP -> FROM SERVER:
220 hostname ESMTP hostname; Sat Feb 9 12:02:13 2008
SMTP -> get_lines(): $data was ""
SMTP -> get_lines(): $str is "250 Hello, spam sender. Pleased to be wasting your time.
"
SMTP -> get_lines(): $data is "250 Hello, spam sender. Pleased to be wasting your time.
"
SMTP -> FROM SERVER:
250 Hello, spam sender. Pleased to be wasting your time.
SMTP -> get_lines(): $data was ""
SMTP -> get_lines(): $str is "500 5.5.1 Command unrecognized
"
SMTP -> get_lines(): $data is "500 5.5.1 Command unrecognized
"
SMTP -> ERROR: AUTH not accepted from server: 500 5.5.1 Command unrecognized

SMTP -> get_lines(): $data was ""
SMTP -> get_lines(): $str is "250 Ok to start over.
"
SMTP -> get_lines(): $data is "250 Ok to start over.
"
SMTP -> FROM SERVER:
250 Ok to start over.
SMTP -> get_lines(): $data was ""
SMTP -> get_lines(): $str is "250 You are about to try to deliver spam. Your time will be spent, for nothing.
"
SMTP -> get_lines(): $data is "250 You are about to try to deliver spam. Your time will be spent, for nothing.
"
SMTP -> FROM SERVER:
250 You are about to try to deliver spam. Your time will be spent, for nothing.
SMTP -> get_lines(): $data was ""
SMTP -> get_lines(): $str is "451 Temporary failure, please try again later.
"
SMTP -> get_lines(): $data is "451 Temporary failure, please try again later.
"
SMTP -> FROM SERVER:
451 Temporary failure, please try again later.
SMTP -> ERROR: RCPT not accepted from server: 451 Temporary failure, please try again later.

SMTP -> FROM SERVER:
SMTP -> ERROR: RSET failed:

Just an update.. So, maybe what I'm seeing is some improperly set up greylisting spam filtering? The kind that requires two sends to go? If this is so, where would the issue be best resolved, that the message be queued for re-attempted delivery? Is that a drupal smtp module function, phpmailer, or my host?

The above debug dump was when I configured a new, remote smtp host. Having just retried the same thing (about 20min later), my message went through! (whereas on my previous host and post, it never did go through.. almost like a blacklist, not a dynamic grey list).

thoughts?

I am not working with SMTP Auth on 5.x anymore and want to help de-clutter your queue. (fwiw, I never resolved my issue)