Headers in body email from Contact Form

Hi all,

i'm italian and new about this forum.
I try to explain the problem.

I got in my website a contact form generated by the Drupal Core module Contact.
When i send the form to a Gmail account there is no problem
But when i send the form to a general domain email (es. info@pippo.it) i can read in the email body some header informations

This is what i see in the email

MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8; format=flowed; delsp=yes
Content-Transfer-Encoding: 8Bit
X-Mailer: Drupal
Errors-To: xxxxxxxxxxx@gmail.com
Sender: xxxxxxxxxxxxxx@gmail.com
From: info@pippo.it
Message-Id: <20100220084219.74A533936D@smtp3.emediaweb.it>
Date: Sat, 20 Feb 2010 09:42:19 +0100 (CET)

if i check the email code i see this

Delivered-To: xxxxxxxxxxxxxxx@gmail.com
Received: by 10.229.87.212 with SMTP id x20cs211371qcl;
Sat, 20 Feb 2010 00:43:55 -0800 (PST)
Received: by 10.229.220.4 with SMTP id hw4mr126229qcb.25.1266655432935;
Sat, 20 Feb 2010 00:43:52 -0800 (PST)
Received-SPF: neutral (google.com: 83.211.223.132 is neither permitted nor denied by best guess record for domain of studiopetrone.com) client-ip=83.211.223.132;
Message-ID: <4b7fa0c7.0ec1f10a.218a.029bMFETCHER_ADDED@google.com>
Received: by 10.241.193.14 with POP3 id 14mf49267qwa.66;
Sat, 20 Feb 2010 00:43:51 -0800 (PST)
X-Gmail-Fetch-Info: info@pippo.it 1 mail.pippo.it 110 info@pippo.it
Received: (qmail 11799 invoked from network); 20 Feb 2010 09:42:19 +0100
Received: from firewall.emedia-web.it (HELO studiopetrone.com) (83.211.223.132)
by host67-168-149-62.serverdedicati.aruba.it with (DHE-RSA-AES256-SHA encrypted) SMTP; 20 Feb 2010 09:42:19 +0100
Received: by studiopetrone.com (Postfix, from userid 48)
id 74A533936D; Sat, 20 Feb 2010 09:42:19 +0100 (CET)
To: info@pippo.it
Subject: [materiali] prova
X-PHP-Originating-Script: 532:mail.inc

MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8; format=flowed; delsp=yes
Content-Transfer-Encoding: 8Bit
X-Mailer: Drupal
Errors-To: xxxxxxxxxxxxxxx@gmail.com
Sender: xxxxxxxxxxxxxxx@gmail.com
From: info@pippo.it
Message-Id: <20100220084219.74A533936D@smtp3.emediaweb.it>
Date: Sat, 20 Feb 2010 09:42:19 +0100 (CET)

Sergio ha inviato un messaggio usando il modulo di contatto
http://www.graphicsrl.it/contact.

prova

there is a blank line between
X-PHP-Originating-Script: 532:mail.inc

and

MIME-Version: 1.0

i think this is the problem
why?