O e-mail usuario@underliux foi desativado?

Olha isso, an tes eu mandava um e-mail para duca@underlinux e tava funfando mas agora...
Código :
Hi. This is the qmail-send program at yahoo.com.
I'm afraid I wasn't able to deliver your message to the following 
addresses.
This is a permanent error; I've given up. Sorry it didn't work out.
 
<[email protected]>:
64.233.185.27 does not like recipient.
Remote host said: 550 5.7.1 No such user 35si1793754wra
Giving up on 64.233.185.27.
 
--- Below this line is a copy of the message.
 
Return-Path: <[email protected]>
Received: (qmail 52348 invoked by uid 60001); 7 Jun 2006 18:00:32 -0000
DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws;
 s=s1024; d=yahoo.com.br;
 
h=Message-ID:Received:Date:From:Subject:To:MIME-Version:Content-Type:Content-Transfer-Encoding;
 
b=ggl2AMBxm478eJTgmKkJYCPganurzNFIQG/fIwmByO8xMkPJ35n1qC8ITte+6/kVEA5qSJEHvrL4NqnchKeOzwDHqSfVkHdxuxCHF10bISrwXN8UOI3YmQ1V0dk8MNaNibZuBzDQVc3IUf2c1gPX0VglkQjZv+C24VI+6fw1V6I= 
;
Message-ID: <[email protected]>
Received: from [200.223.200.210] by web50104.mail.yahoo.com via HTTP; 
Wed, 07 Jun 2006 15:00:31 ART
Date: Wed, 7 Jun 2006 15:00:31 -0300 (ART)
From: Eduardo Costa <[email protected]>
Subject: teste
To: [email][email protected][/email]
MIME-Version: 1.0
Content-Type: multipart/alternative; 
boundary="0-1897300613-1149703231=:48381"
Content-Transfer-Encoding: 8bit
 
--0-1897300613-1149703231=:48381
Content-Type: text/plain; charset=iso-8859-1
Content-Transfer-Encoding: 8bit
 
teste :-)
Ab, Duca :-)