Problème avec ajax

Bonjour,

Je veux faire une mise à jour d'une page avec ajax, mais j'ai un problème de code.Pouvez-vous m'aider s'il vous plait?Merci d'avance pour votre collaboration!
Voici mon code:

<?php
// print_r($_POST);
require_once 'config.php';

$query = "SELECT * FROM membres";

$filtre = array();

if(isset($_POST["nom"]) && $_POST["nom"] != "")
$filtre[] = sprintf("'nom' LIKE '%s' OR 'prenom' LIKE '%s'", "%".$_POST["nom"]."%", "%".$_POST["nom"]."%");
if(isset($_POST["civilite"]) && $_POST["civilite"] != "")
$filtre[] = sprintf("'civilite' = '%s'", $_POST["civilite"]);

if(count($filtre) != 0)
$query = $query." WHERE ".implode(" AND ", $filtre);

if(isset($_GET["page"]))
$page = $_GET["page"];
else
$page = 0;

$par_page = 3;


$res = mysql_query($query);
$num_rows = mysql_num_rows($res);
echo "$num_rows Enregistrements\n";
$query = sprintf("%s LIMIT %d, %d", $query, $page*$par_page, $par_page);

//echo $query;

$res = mysql_query($query) OR die (mysql_error());
?>

<script language="javascript">
function confirme(){
var confirmation = confirm("Voulez vous vraiment supprimer cette personne?");
if(confirmation){
return true;
}
return false;
}
function affichage(param){
var new_action = param.href;//le tery ambany
document.getElementById("filtre").action = new_action; //soloina ny action anle forme
document.getElementById("filtre").submit();
return false;
}

</script>
<script type="text/javascript" src="scripts/jquery-1.4.2.min.js">

</script>
<form method="post" action="liste.php" id="filtre">
<table cellpadding="0" cellspacing="0">
<tr><td><a href="form.php">Formulaire</td></tr>
<tr align="left">
<td>Rechercher par nom: </td>
<td><input type="text" name="nom" id="filtre" value="<?php if(isset($_POST["nom"])) echo $_POST["nom"]; ?>"></td>
<td><input type="submit" name="cherche" value="Chercher"<?php if(isset($_POST["cherche"])) echo $filtre; ?>></td>
</tr>
<td>Rechercher tous les: </td>
<td><select name="civilite">
<option value="" <?php if(isset($_POST["civilite"]) && $_POST["civilite"] == ""){ echo 'selected="selected"'; } ?>>Tous</option>
<option value="Mr" <?php if(isset($_POST["civilite"]) && $_POST["civilite"] == "Mr"){ echo 'selected="selected"'; } ?>>Mr</option>
<option value="Mme" <?php if(isset($_POST["civilite"]) && $_POST["civilite"] == "Mme"){ echo 'selected="selected"'; } ?>>Mme</option>
<option value="Mlle" <?php if(isset($_POST["civilite"]) && $_POST["civilite"] == "Mlle"){ echo 'selected="selected"';} ?>>Mlle</option>
</select></td>
</tr>
</table>
</form>
<table width="100%" border="1">
<?php if(isset($_GET["msg"])) :?>
<tr>
<td colspan="10">
<?php echo $_GET["msg"]; ?>
</td>
</tr>
<?php endif ?>
<tr>
<th width="2">Civilité</th>
<th width="50" align="center">Nom</th>
<th width="20" align="center">Prénom</th>
<th width="20" align="center">Date de naissance</th>
<th width="20" align="center">Profession</th>
<th width="20" align="center">Ville</th>
<th width="3" align="center">Code Postal</th>
<th width="20" align="center">Téléphone</th>
<th width="5" align="center">E-mail</th>
<th width="5" align="center">Action</th>
</tr>
<?php
while($data = mysql_fetch_array($res)){
?>

<tr valign="top">
<td align="center" class="td1"><?php echo $data["civilite"];?></td>
<td align="center" class="td2"><strong><?php echo $data["nom"]; ?></strong></td>
<td align="center" class="td3"><i><?php echo $data["prenom"]; ?></i></td>
<td align="center" class="td4"><?php echo $data["date_nais"]; ?></td>
<td align="center" class="td5"><?php echo $data["profession"]; ?></a></td>
<td align="center" class="td6"><?php echo $data["ville"]; ?></td>
<td align="center" class="td7"><?php echo $data["cp"]; ?></td>
<td align="center" class="td8"><?php echo $data["telephone"]; ?></td>
<td align="center" class="td9"><?php echo $data["email"]; ?></td>
<td align="center" class="td8"><a href="maj.php?id_membre=<?php echo $data["id_membre"]; ?>"><a href="javascript:void(0);" id="filtre">Editer</a></a>   
<script type="text/javascript" src="http://code.jquery.com/jquery-latest.js"></script>
<script type="text/javascript">
$('#a').click(function(){
$.ajax({
'async': 'true',
'type': 'POST',
'url': 'maj.php',
success: function(response){
var idmem = document.getElementById("filtre");
}
});
});
</script>
<script type="text/javascript">$("#id_membre");</script>
<a href="supprime.php?id_membre=<?php echo $data["id_membre"]; ?>"onclick="return confirme();">Supprimer</a></td>
</td>
</tr>
<?php } ?>
</table>

<table>
<tr align="center">
<td>
<?php
$nb_page = ceil($num_rows/$par_page);
for($i=0; $i<$nb_page; $i++){
if($page == $i){
echo "$i";
}else
//echo '<a href="liste.php?page='."".$i.'"> '.$i.' </a>';
echo '<a href="liste.php?page='."".$i.'" onclick="return affichage(this);"> '.$i.' </a>';
}
?>
</td>
</tr>
</table>

Cordialement!
mirakanto