Undelivered Mail?

Hej,

Jeg har forsøgt at sende en e-mail, men har fået denne mail tilbage fra mailerdeamon. Hvorfor?

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This is the Postfix program at host pfepb.post.tele.dk.

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

<kundeservice@japanphoto.dk>: host mail.japanphoto.dk[217.118.34.250] said: 554
    Message contains known spam source in Received: header (in reply to end of
    DATA command)