Problème avec un INSERT INTO php

<form method="POST" action=""> 
Nom:*<br/><input type="text" name="nom" value=""><br/> 
Prenom:*<br/><input type="text" name="prenom" value=""><br/> 
Ville:<br/><input type="text" name="ville" value=""><br/> 
Adresse:<br/><TEXTAREA name="adresse"></TEXTAREA><br/> 
Code postal:<br/><input type="text" name="code_postal" value=""><br/> 
Téléphone:*<br/><input type="text" name="telephone" value=""><br/> 
Email:*<br/><input type="text" name="email_contact" value=""><br/> 
Message:*<br/><TEXTAREA name="message"></TEXTAREA><br/><br/><br/> 
<input type="submit" name="envoyer" value="Envoyer"> 
</form> 

<?php 
if (isset($_POST['envoyer']))  
{ 
 extract($_POST); 
 $_SESSION[nom] = $nom; 
 $_SESSION[prenom] = $prenom; 
 $_SESSION[adresse] = $adresse; 
 $_SESSION[code_postal] = $code_postal; 
 $_SESSION[ville] = $ville; 
 $_SESSION[email_contact] = $email_contact; 
 $_SESSION[telephone] = $telephone; 
 $_SESSION[message] = $message; 
 $message = ""; 

 $mail=verifEmail($email_contact); 
 if($mail == null AND $mail == "") 
 { 
  $message .= "Adresse Email non valide \\n"; 
  echo $_SESSION [email_contact]; 
 } 
 if ($prenom== null AND $prenom == "")  
 { 
  $message .= "Prenom non valide \\n"; 
  echo $_SESSION [prenom]; 
 } 
 if ($nom== null AND $nom == "") 
 { 
  $message .= "Nom non valide \\n"; 
  echo $_SESSION [nom]; 
 } 

 if ($code_postal==null AND $code_postal=="" AND strlen(code_postal)!=5)  
 { 
  $message .= "Code postal non valide \\n"; 
  echo $_SESSION [Code_postal]; 
 } 

 if ($ville==null AND $ville=="")  
 { 
  $message .= "ville non valide \\n"; 
  echo $_SESSION [ville]; 
 } 

 if ($telephone==null AND $telephone=="" AND strlen(telephone)<10 AND strlen(telephone)>15)  
 { 
  $message .= "Téléphone non valide \\n"; 
  echo $_SESSION [telephone]; 
 } 

 if ($adresse==null AND $adresse=="")  
 { 
  $message .= "Adresse non valide \\n"; 
  echo $_SESSION [adresse]; 
 } 

 if ($message != "")  
 { 
  echo popUp($message); 
  echo $_SESSION [message]; 

 } 
 else 
 { 
  mysql_connect("localhost", "root", "root"); 
  mysql_select_db("projet_bdd"); 
  $requete_insert = "INSERT INTO contact VALUES '".$telephone."', '".$ville."', '".$nom."', '".$prenom."', '".$email_contact."', '".$adresse."', '".$code_postal."', '".$message."'"; 
  $resultat_insert = query($requete_insert); 

  unset($_SESSION['nom']); 
  unset($_SESSION['prenom']); 
  unset($_SESSION['adresse']); 
  unset($_SESSION['code_postal']); 
  unset($_SESSION['email_contact']); 
  unset($_SESSION['ville']); 
  unset($_SESSION['telephone']); 
  unset($_SESSION['message']); 
   
   
 } 
 /*refresh(0, "php", "index?page=gestion_repertoire");*/ 

} 
?>

function query($req)
{
	$resultat = mysql_query($req);
	return $resultat;
}