[JavaScript][Firefox3.5] geolocation の使い方

if (navigator.geolocation) {  
   /* geolocation is available */
  navigator.geolocation.getCurrentPosition(function(position) {
    alert(position.coords.latitude + ":" + position.coords.longitude);
  });
} else {  
   alert("I'm sorry, but geolocation services are not supported by your browser.");  
}