magazine competition

[mackemsrule]

Hi, I've just received the latest issue off the postie and I've tried to enter the framing competition,however I just get delivery reports saying that there's an error and the mailbox doesn't exist, I even tried the magazines main email dphotographer@imagine-publishing.co.uk
I've tried through google mail, sky mail and my hotmail account.
Can anyone help me?
Everytime I receive back this:-
This is an informative message sent by mail.imagine-publishing.co.uk.

The server was not able to deliver your email message

Subject: Framing
Date: Wed, 13 Jun 2012 12:24:45 +0100

to the following addresses:

<competition@dphotographer.co.uk> (mail.imagine-publishing.co.uk: Mailbox does not exist)
Original-Recipient:
Final-Recipient: rfc822;competition@dphotographer.co.uk
Action: failure
Status: 5.1.1
Diagnostic-Code: SMTP; Mailbox does not exist