I run a mail server managing example.it domain.

When I send an email to a Hotmail account, Hotmail puts my email into the spam folder.

Other providers works good with emails coming from my mail server.

I can't find out the motivation.

This is the header of an email from my server to daniele.#*$!#*$!x@hotmail.com:

X-Message-Status: n:0
X-SID-PRA: Staff di Example.it <staff.example@example.it>
X-Message-Info: txF49lGdW41ZQMT/YGAwEd/pztdlCG6jP2Wssa/bBUI=
Received: from sm-server.example.it ([62.149.#*$!.#*$!]) by bay0-mc6-f1.bay0.hotmail.com with Microsoft SMTPSVC(6.0.3790.2444);
Mon, 26 Feb 2007 03:10:47 -0800
Received: from localhost
([127.0.0.1] helo=www.example.it ident=www-data)
by sm-server.example.it with esmtp (Exim 4.50)
id 1HLdm8-0000rH-U1
for daniele.#*$!#*$!x@hotmail.com; Mon, 26 Feb 2007 12:12:12 +0100
Date: Mon, 26 Feb 2007 12:12:12 +0100
To: daniele.#*$!#*$!#*$!@hotmail.com
From: "Staff di Example.it" <staff.example@example.it>
Subject: prova3
Message-ID: <62e858c7f49585b67196e4febf8caf33@www.example.it>
X-Priority: 3
X-Mailer: PHPMailer [version 1.73]
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Content-Type: text/html; charset="iso-8859-1"
Return-Path: staff.example@example.it
X-OriginalArrivalTime: 26 Feb 2007 11:10:48.0677 (UTC) FILETIME=[C4E6B950:01C75996]

Can anyone help me?

Thanks in advance,
Daniele