strange error... any idea?

[Kelly Hamlin]

Someone trying to sendmail to me is getting the following message and i
wasnt sure if it was caused by relay or whatnot..

SMTP error from remote mailer after MAIL FROM: info at fintastic.com :
550 5.7.1 Access denied


Ive done some research and it all points to mail relaying, however ive check
the server 207.178.136.124 (mail.usemail.com) and it doesnt appear in any of
the black lists on mail-abuse.org, or ordb.org. Anyone have any clues on
what might be causing this?
thanks, and im sorry i know its not a mailscanner problem most likely, but
im desprate :)
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                ( o o )
+--.oooO--(_)--Oooo.-----------------+
| [Kelly Hamlin]
| kellyh at cyberstreet.com
| http://www.bomb.net
|   .oooO
|      (  )    Oooo.
+--- \  (----(   )----------------------------+
          \_)    ) /
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