No marker is displayed on google map api v3

I am trying to use Google Map api v3 to render a map which will contain a groupe of locations. The data Lat and Lng are both stored in one field in my db called “Map” (screen)

Project table code

    CREATE TABLE IF NOT EXISTS `project` (
      `Id` varchar(255) NOT NULL,
      `Type` varchar(20) NOT NULL default '',
      `Location` varchar(50) NOT NULL default '',
      `Map` text,
      ........
    ) ENGINE=MyISAM DEFAULT CHARSET=utf8;

I followed the Google Developper’s tutorial on how to Use PHP/MySQL with Google Maps
The XML file is generated and works fine, but when I try to use it, no marker is displayed in the map. The map is empty.
No error is reported by fierbug or chrome console

The phpsqlajax_genxml code

     <?php

        require("phpsqlajax_dbinfo.php");

        // Start XML file, create parent node

        $dom = new DOMDocument("1.0");
        $node = $dom->createElement("project");
        $parnode = $dom->appendChild($node);

        // Opens a connection to a MySQL server

        $connection=mysql_connect ('localhost', $username, $password);
        if (!$connection) {  die('Not connected : ' . mysql_error());}

        // Set the active MySQL database

        $db_selected = mysql_select_db($database, $connection);
        if (!$db_selected) {
          die ('Can\\'t use db : ' . mysql_error());
        }

        // Select all the rows in the project table

        $query = "SELECT * FROM project WHERE 1";
        $result = mysql_query($query);
        if (!$result) {
          die('Invalid query: ' . mysql_error());
        }

        header("Content-type: text/xml");

        // Iterate through the rows, adding XML nodes for each

        while ($row = @mysql_fetch_assoc($result)){
          // ADD TO XML DOCUMENT NODE
          $node = $dom->createElement("marker");
          $newnode = $parnode->appendChild($node);
          $newnode->setAttribute("Id",$row['Id']);
          $newnode->setAttribute("Location", $row['Location']);
          $newnode->setAttribute("Map", $row['Map']);
          $newnode->setAttribute("Map", $row['Map']);
          $newnode->setAttribute("Type", $row['Type']);
        }

        echo $dom->saveXML();

        ?>

The Javascript code

    <!DOCTYPE html >
      <head>
        <meta name="viewport" content="initial-scale=1.0, user-scalable=no" />
        <meta http-equiv="content-type" content="text/html; charset=UTF-8"/>
        <script type="text/javascript" src="http://maps.googleapis.com/maps/api/js?sensor=false"></script>
        <script type="text/javascript">
        //<![CDATA[
        var customIcons = {
          apartment: {icon: 'http://labs.google.com/ridefinder/images/mm_20_blue.png'},
          service_apartment: {icon: 'http://labs.google.com/ridefinder/images/mm_20_red.png'},
          condo: {icon: 'http://labs.google.com/ridefinder/images/mm_20_orange.png'}
        };
        function load() {
          var map = new google.maps.Map(document.getElementById("map"), {
            center: new google.maps.LatLng(13.732304,100.567122),
            zoom: 13,
            mapTypeId: 'roadmap'
          });
          var infoWindow = new google.maps.InfoWindow;
          // Change this depending on the name of your PHP file
          downloadUrl("phpsqlajax_genxml.php", function(data) {
            var xml = data.responseXML;
            var project = xml.documentElement.getElementsByTagName("marker");
            for (var i = 0; i < project.length; i++) {
              var Id = project[i].getAttribute("Id");
              var Location = project[i].getAttribute("Location");
              var Type = project[i].getAttribute("Type");
              var point = new google.maps.LatLng(
                  parseFloat(project[i].getAttribute("Map")),
                  parseFloat(project[i].getAttribute("Map")));
              var html = "<b>" + Id + "</b> <br/>" + Location;
              var icon = customIcons[Type] || {};
              var marker = new google.maps.Marker({
                map: map,
                position: point,
                icon: icon.icon
              });
              bindInfoWindow(marker, map, infoWindow, html);
            }
          });
        }
        function bindInfoWindow(marker, map, infoWindow, html) {
          google.maps.event.addListener(marker, 'click', function() {
            infoWindow.setContent(html);
            infoWindow.open(map, marker);
          });
        }
        function downloadUrl(url, callback) {
          var request = window.ActiveXObject ?
              new ActiveXObject('Microsoft.XMLHTTP') :
              new XMLHttpRequest;
          request.onreadystatechange = function() {
            if (request.readyState == 4) {
              request.onreadystatechange = doNothing;
              callback(request, request.status);
            }
          };
          request.open('GET', url, true);
          request.send(null);
        }
        function doNothing() {}
        //]]>
      </script>
      </head>
      <body onload="load()">
        <div id="map" style="width: 1138px; height: 800px"></div>
      </body>
    </html>

The XML generated code

        <project>
        <marker Id="******" Location="*****" Map="a:5:{s:9:"CenterLat";s:18:"13.723127876409816";s:9:"CenterLng";s:18:"100.52852128985683";s:4:"Zoom";s:2:"16";s:9:"MarkerLat";s:18:"13.722750766481905";s:9:"MarkerLng";s:18:"100.52785811367796";}" Type="service_apartment"/>
    ......

please any help or suggestion would be much appreciate
thank you