Postfix...Urgente

Bom Dia..pessoal......eu estou com um tremendo problema com o postfix....é o seguinte...antes ele mandava e-mail normalmente para o zipmail........agora ele não consegue mandar de jeito nenhum.....e da a seguinte mensagem....






Em Sex, 2004-06-04 às 08:42, Mail Delivery System escreveu:
> This is the Postfix program at host srvlinux.srv.net.
>
> I'm sorry to have to inform you that the message returned
> below could not be delivered to one or more destinations.
>
> For further assistance, please send mail to <postmaster>
>
> If you do so, please include this problem report. You can
> delete your own text from the message returned below.
>
> The Postfix program
>
> <[email protected]>: host smtp.zipmail.com.br[200.221.11.147] said:
501
> mail not accepted from blacklisted IP address (in reply to MAIL FROM
> command)
>
> ______________________________________________________________________
>
> Reporting-MTA: dns; srvlinux.srv.net
> Arrival-Date: Fri, 4 Jun 2004 08:42:33 -0300 (BRT)
>
> Final-Recipient: rfc822; [email protected]
> Action: failed
> Status: 5.0.0
> Diagnostic-Code: X-Postfix; host smtp.zipmail.com.br[200.221.11.147] said: 501
> mail not accepted from blacklisted IP address (in reply to MAIL FROM
> command)
>
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