Email ...no Yahoo Emails Go Through

I was wondering if some of you more seasoned techie's can help me. I have a reseller hosting account and one of my clients is having issues with getting any email that is sent from any yahoo email account to her domain email. I have personally tried to send an email from my yahoo account to her domain email and here is the error I got back. None of my other clients has the issue. This is a new account by the way.

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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.

<andrea@jazzinaroundfarm.com>:
Sorry, I wasn't able to establish an SMTP connection. (#4.4.1)
I'm not going to try again; this message has been in the queue too long.

--- Below this line is a copy of the message.

Return-Path: <helpahorse24053@yahoo.com>
Received: (qmail 41845 invoked by uid 60001); 19 Sep 2007 21:20:30 -0000
DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws;
s=s1024; d=yahoo.com;
h=X-YMail-OSG:Receivedate:Fromubject:To:MIME-Version:Content-Type:Content-Transfer-Encoding:Message-ID;
b=iHu3WMU1gy5851VB+uyII7S0C2aOM3g6TEYnsWmtIWTwFLEJAI67A28e6mchNTTyfX3ioPZ9rl9TmA3l8J0YDPCDWWZcGMKqhVFco6nIHkaCVpF6ALXJ7q41VxHsn+nYFnb5UUpgVZ7lk+RDIyjv 70wiO+xmqzEXO/OAzEXvi0E=;
X-YMail-OSG: smDGXoAVM1lr_heTahTlEwmcKX4NEdCpvRAoON1.hOTrI6lWRVaNB0vUqOXD7pOWmadYN8I4vlXjvYS2W2xVQsH0rw--
Received: from [71.51.18.67] by web35804.mail.mud.yahoo.com via HTTP; Wed, 19 Sep 2007 14:20:30 PDT
Date: Wed, 19 Sep 2007 14:20:30 -0700 (PDT)
From: betty haynes <helpahorse24053@yahoo.com>
Subject: testing to see if this comes through...this is Betty
To: andrea@jazzinaroundfarm.com
MIME-Version: 1.0
Content-Type: multipart/alternative; boundary="0-1780532074-1190236830=:41745"
Content-Transfer-Encoding: 8bit
Message-ID: <315189.41745.qm@web35804.mail.mud.yahoo.com>

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Content-Type: text/plain; charset=iso-8859-1
Content-Transfer-Encoding: 8bit

Just seeing if this comes through via my yahoo addy.

4-the-luv-of-a-critter
Please check out our new animal placement web site. It is a free service for anyone who is looking to place their pets in a new home.We list any animal regardless of species, breed, age etc .Our service is also used for those looking for that new pet. For more information please see our web site at [url]

Low Cost Web Design & Hosting [url]

My animals are the reason I live and breathe. With out them in my life I would just as soon be dead !---Betty Haynes

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Content-Type: text/html; charset=iso-8859-1
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Just seeing if this comes through via my yahoo addy.<BR><BR><FONT color=#a040ff> <DIV>4-the-luv-of-a-critter <BR>Please check out our new animal placement web site. It is a free service for anyone who is looking to place their pets in a new home.We list any animal regardless of species, breed, age etc .Our service is also used for those looking for that new pet. For more information please see our web site at <A href="http://www.4-the-luv-of-a-critter.com/">[url]</A> </DIV> <DIV>&nbsp;</DIV> <DIV>Low Cost Web Design &amp; Hosting <A href="[url]">[url]</A> </DIV> <DIV>&nbsp;</DIV> <DIV>My animals are the reason I live and breathe. With out them in my life I would just as soon be dead !---Betty Haynes</DIV> <DIV>&nbsp;</DIV> <DIV>&nbsp;</DIV></FONT>
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