Problemer med at sende mail.

Jeg har installeret hylafax og på en suse 9.1.
Hvergang den modtager en fax skal den sende en mail.
Det virker også fint så længe jeg sender til en bruger eg. root.
Men hvis jeg sender til extern email kommer den ikke igennem. Til gengæld for min fax bruger den mail.

From MAILER-DAEMON  Wed Sep  8 10:42:53 2004
X-Original-To: fax@linux.site
Delivered-To: fax@linux.site
Date: Wed,  8 Sep 2004 10:42:53 +0200 (CEST)
From: MAILER-DAEMON@linux.site (Mail Delivery System)
Subject: Undelivered Mail Returned to Sender
To: fax@linux.site
MIME-Version: 1.0
Content-Type: multipart/report; report-type=delivery-status;
        boundary="0390619C53.1094632973/linux.site"


Part 1:
Content-Description: Notification
Content-Type: text/plain

This is the Postfix program at host linux.site.

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

<rasmus.stokholm@get2net.dk>: host mailgw.swip.net[212.247.156.1] said: 572
    fax@linux.site host name is unknown (in reply to MAIL FROM command)

Part 2:
Content-Description: Delivery report
Content-Type: message/delivery-status

Nogen der har en ide til hvordan man løser den ?