Relay Access Denied ; POSTFIX FC4 Server

[CHAT KHODA]

Dear friend,
Recently we have upgraded an old MsExchange machine to
FC4 and Postfix 2.2.2 .We have no problem with our
webmail,squirrel mail and it pop service works fine
when we want to retrieve messages from the server but
when we want to send email to outside world,like lycos
mail boxes,we got Relat access denied.
I have studied documents and it seems to me that the
reason refers to the default amount of $relay_domains
which is equal to $mydestination.

Do you have any idea to solve this probem and enable
our users to send their emails via outlook AND keep
out server protected against SPAMMERS.

Thank you,


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