Open Relay Problem From Hell

Hi

I’m having a lot of troubel locking down a mail server I’m looking after.
Its running osX 10.1.4 and I’m being harrassed by a number of Spammers using the thing as an open relay.

I’ve tried the various procedures in the apple documentation.

http://docs.info.apple.com/article.html?artnum=106762
http://docs.info.apple.com/article.html?artnum=106760

I can either lock the machine down so you can send only or I fail this test
telnet relay-test.mail-abuse.org

anyone else having this problem?

Anyone have any idea what I’m doing wrong?

TIA

nevets