function writediv(text){
    document.getElementById('mediabox').innerHTML = text;
  }

  function file(fichier){
    if(window.XMLHttpRequest) // FIREFOX
        xhr_object = new XMLHttpRequest();
    else if(window.ActiveXObject) // IE
        xhr_object = new ActiveXObject("Microsoft.XMLHTTP");
    else
        return(false);
    xhr_object.open("GET", fichier, false);
    xhr_object.send(null);
    if(xhr_object.readyState == 4) return(xhr_object.responseText);
    else return(false);
  }

  function ajax(param){
    //text = file('http://www.editeurjavascript.com/scripts/examples/verifpseudo.php?pseudo='+escape(pseudo));
    text = file('http://www.marine.org.au/scripts/media_lister/media_ajax.php'+param);
    writediv(text);
  }