envoyer un mail avec php

<?php

 
$destinataire= "monaddresse@domaine.fr";

$objet = "Formulaire de contact";

$headers = "From: monsite.fr\n\r";

$headers .= "MIME-Version: 1.0\n\r";

$headers .= "Content-Type: text/html; charset=iso-8859-1\n\r";

 
$nom = $_POST['nom'];

$prenom = $_POST['prenom'];

$societe = $_POST['societe'];

$fonction = $_POST['fonction'];

$e_mail = $_POST['e_mail'];

$code_postal = $_POST['code_postal'];

$ville = $_POST['ville'];

$telephone = $_POST['telephone'];

$message = $_POST['message'];

 
$msg = "nom = $nom

prenom = $prenom

societe = $societe

fonction = $fonction

email = $e_mail

code_postal = $code_postal

ville = $ville

telephone = $telephone

message = $message";

 
echo nl2br($msg);

 
mail($destinataire, $objet, $headers, $msg);

echo "formulaire envoyé.";

 
?>

Warning: mail(): Failed to connect to mailserver at "localhost" port 25, verify your "SMTP" and "smtp_port" setting in php.ini or use ini_set() in c:\documents and settings\jno\bureau\cours\siteauberge\form.php on line 55