Msn.co.uk MX tag..broken? hacked?

just noticed something wierd which i don't understand so figured i'd ask the smart guys n gals around here.. why is the MX record for msn.co.uk set to depot.dial.pipex.com, with the result that attempting to send mail bounces with "relay access denied"? tried from a few places (http://www.google.com/search?q=nslookup) and it's not just me.. something screwed up in the DNS..? maliciously? # dig msn.co.uk MX ... ;; ANSWER SECTION: msn.co.uk. 778 IN MX 20 depot.dial.pipex.com. # telnet depot.dial.pipex.com 25 Trying 62.241.162.96... Connected to depot.dial.pipex.com (62.241.162.96). Escape character is '^]'. 220 addams.systems.pipex.net ESMTP Postfix EHLO ... MAIL FROM: ... 250 Ok RCPT TO: <test@msn.co.uk> 554 <test@msn.co.uk>: Relay access denied