Can't receive email

[merlincc]

I have followed the perfect setup for fedora core 6. I have setup a site and an email address. I have tested telneting to localhost and all test pass.

I can connect to webmail and I sent a test messgae to my work email account. It worked just fine.

I then sent an email from my work email account to my new email address and I get this in the maillog:

Dec 4 17:28:16 kelly postfix/smtpd[3392]: NOQUEUE: reject: RCPT from sp-internet-ext-ply.uhc.com[198.203.175.175]: 554 5.7.1 <john@4thegreens.com>: Relay access denied; from=<john_green@uhc.com> to=<john@4thegreens.com> proto=ESMTP helo=<firewall-cluster.uhc.com>

I have searched the forums and have tried several things but nothing works. I have tried removing the site and recreating. I have redone the postfix stuff from the perfect setup guide. Nothing works.

Where can I look now?

Thanks.