// Opens the caller's default e-mail client
// with the subject filled if specified.
function LoadGMap(id, lat, lng, zoom, markerFile)
{
 if (GBrowserIsCompatible()) {
  var map = new GMap2(document.getElementById(id));
  map.addControl(new GSmallMapControl());
  map.addControl(new GMapTypeControl());
  map.setCenter(new GLatLng(lat,lng), zoom);
  GDownloadUrl(markerFile, function(data, responseCode)
  {
  var xml = GXml.parse(data); 
  var markers = xml.documentElement.getElementsByTagName('marker');
  for (var i = 0; i < markers.length; i++)
  {
  var point = new GLatLng(parseFloat(markers[i].getAttribute('lat')),
  parseFloat(markers[i].getAttribute('lng')));
  map.addOverlay(new GMarker(point));
  }
  });
  }
}