hi
from when i put in "mailer settings" "smtp server"
the emails from people registration are coming back sometimes (quite often)
and I recive emails like that:

This message was created automatically by mail delivery software.

A message that you sent could not be delivered to one or more of its recipients. This is a permanent error. The following address(es) failed:

xxx@hotmail.com
Unrouteable address

---

This is a copy of the message, including all the headers.

---

Return-path: <xxx@xxx.eu>
Received: from localhost ([127.0.0.1] helo=www.xxx.eu)
by lnx6.xxx.it with esmtpa (Exim 4.67)
(envelope-from <admin@xxx.eu>)
id 1L8Flo-00048Y-Ib
for xxx@hotmail.com; Thu, 04 Dec 2008 16:05:36 +0100
Date: Thu, 4 Dec 2008 16:05:36 +0100
To: xxx@hotmail.com
From: xxx - User Registration <admin@xxx.eu>
Reply-To: xxx - User Registration <admin@xxx.eu>
Subject: xxxY - xxx Team - Your Registration is Pending Approval
Message-ID: <9eae637b59fc6e3ff939f0471ba238fe@www.xxx.eu>
X-Priority: 3
X-Mailer: PHPMailer (phpmailer.sourceforge.net) [version 2.0.0 rc3]
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Content-Type: text/plain; charset="UTF-8"

Greetings xxx,

Thank you for applying for registration with us.
xxx Team your request and we will process it as soon as you confirm your email address by clicking on the following
hyperlink:

CLICK TO CONFIRM -->
www.xxx.eu/index.php?option=com_comprofiler&task=confirm&confirmcode=reg850ffa1094fb8d06509e96d225a70e3305c0f7de



Once your email address is confirmed you'll can JOIN all'our Erasmus Community!

You will be notified by email of the progress of your registration process.

Your details:
Email : xxx@hotmail.com
Username : xxx



xxx Team


NOTE: This email was automatically generated from xxx INTERNATIONAL COMMUNITY (www.xxx.eu).

somebody could helpme how to solve?
thnx