Returned E-mail-(helo/hostname mismatch)

I have a user that received a bounce back with the following:

“Recipient address rejected: Mail appeared to be SPAM or forged. Ask your Mail/DNS-Administrator to corect HELO and DNS MX settings or to get removed from DNSBLs;”

I am using Exchange 2003 with a Front End Web Server.
the MTA HELO resolved as my Server name, and the MTA hostname resolved as my OWA URL.

is this something I can fix on my end, or do I simply need to request to be taken off of their Black List?

thanks