[Exim] Exim error (help-me)

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Hi,
The server return me the error:
    "550 relaying to <name@???> prohibited by administrator (failed to find host name from IP address), porta: 25, Secure (SSL): não, Erro de servidor:550,número do erro: 0x800CCC79"

I use Exim with a local network with two gateways, in the first gateway were the server are, it's working, but the other gateway return the error when i send a mail out the local network.

Can you help-me?

Thanks

Nuno Morg
(nuno.morgado@???)
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