"Relay access denied" for email received (using @ in mailbox usernames)

For email I use the option setup using "Format for usernames that include domain", select "user@domain."

When I send an e-mail from outside my server to test@czechmission.com I am getting the following error in /var/log/maillog

Jan 7 14:35:27 li46-122 postfix/smtpd[3077]: connect from fed1rmmtao106.cox.net[68.230.241.40]
Jan 7 14:35:28 li46-122 postfix/smtpd[3077]: NOQUEUE: reject: RCPT from fed1rmmtao106.cox.net[68.230.241.40]: 554 5.7.1 : Relay access denied; from= to= proto=ESMTP helo=
Jan 7 14:35:28 li46-122 postfix/smtpd[3077]: disconnect from fed1rmmtao106.cox.net[68.230.241.40]

I read http://www.virtualmin.com/documentation/id,frequently_asked_questions/#w...

and I added this line to /etc/sysconfig/saslauthd:

FLAGS=-rd

I rebooted the system, but the server is still having problems receiving email.

Status: 
Closed (fixed)