PHP - Ajax non funziona

[goxpix]

Salve a tutti, io ho un problema con PHP e Ajax, non funziona nulla. Posto il codice js di Ajax:

function Inint_AJAX() {
try { return new ActiveXObject("Msxml2.XMLHTTP"); } catch(e) {} //IE
try { return new ActiveXObject("Microsoft.XMLHTTP"); } catch(e) {} //IE
try { return new XMLHttpRequest(); } catch(e) {} //Native Javascript
alert("XMLHttpRequest not supported");
return null;
}

function dochange(src, val) {
var req = Inint_AJAX();
req.onreadystatechange = function () {
if (req.readyState==4) {
if (req.status==200) {
document.getElementById(src).innerHTML=req.respons eText;
}
}
};
req.open("GET", "search_ajax.php?data="+src+"&val="+val);
req.setRequestHeader("Content-Type", "application/x-www-form-urlencoded;charset=UTF-8");
req.send(null);
}

window.onLoad=dochange('province', -1);

posto il codice del form:

<div id="search">
<form>
<div class="clear"></div>
<div class="block">
<label>Country</label>
<?php echo " <font id=province><select>\n";
echo "<option value='0'>============</option> \n" ;
echo "</select></font>\n"; ?>

</div>

<div class="block">
<label>Region</label>
<?php echo"<font id=amper><select>\n";
echo "<option value='0'>==== none ====</option> \n" ;
echo "</select></font>\n";?>

</div>

<div class="block">
<label>City</label>
<?php echo "<font id=tumbon><select>\n";
echo "<option value='0'>==== none ====</option> \n" ;
echo "</select></font>\n";?>
</div>
</form>

</div>

Non mi carica + Ajax e non entra nella pagina search_ajax.php. PEr caso é un problema di ID, io nel mio caso ho messo solo province.

Aiuto

[goxpix]

posto il codice PHP:

<?
header ("Expires: Mon, 26 Jul 1997 05:00:00 GMT");
header ("Last-Modified: " . gmdate("D, d M Y H:i:s") . " GMT");
header ("Cache-Control: no-cache, must-revalidate");
header ("Pragma: no-cache");

header("content-type: application/x-javascript; charset=tis-620");

$data=$_GET['data'];
$val=$_GET['val'];

$dbhost = "localhost";
$dbuser = "root";
$dbpass = "1234";
$dbname = "realestate";
mysql_pconnect($dbhost,$dbuser,$dbpass) or die ("Unable to connect to MySQL server");

if ($data=='province') {
echo "<select name='province' onChange=\"dochange('amper', this.value)\">\n";
echo "<option value=''>==== SELECT ====</option>\n";
$result=mysql_db_query($dbname,"select distinct(country) from addresses where detail='1'");
while(list($country)=mysql_fetch_array($result)){
echo "<option value=\"$country\">$country</option> \n" ;
}
} else if ($data=='amper') {
echo "<select name='amper' onChange=\"dochange('tumbon', this.value)\">\n";
echo "<option value=''>======== select ========</option>\n";
$val2=$val;
$val = substr($val,0,2);
$result=mysql_db_query($dbname,"SELECT distinct(state) FROM addresses WHERE detail='1' and country LIKE '$val%' ");
while(list($state)=mysql_fetch_array($result)){
echo "<option value=\"$state\" >$state</option> \n" ;
}
} else if ($data=='tumbon') {
echo "<select name='tumbon' >\n";
echo "<option value=''>======== select ========</option>\n";
$val2=$val;
$val = substr($val,0,4);
$result=mysql_db_query($dbname,"SELECT distinct(city) FROM addresses WHERE
detail='1' and state LIKE '$val%'");
while(list($city)=mysql_fetch_array($result)){
echo "<option value=\"$city\" >$city</option> \n" ;
}
}
echo "</select>\n";
?>