var tasten = '';

function keyPressed (Ereignis) {
  if (!Ereignis)
    Ereignis = window.event;
  if (Ereignis.which) {
    Tastencode = Ereignis.which;
  } else if (Ereignis.keyCode) {
    Tastencode = Ereignis.keyCode;
  }
  
	tasten = tasten + String.fromCharCode(Tastencode);

		new Ajax.Request('passwort.php',
			  {
				method:'post',
				parameters: {bla: tasten},
				onSuccess: function(transport){
				  var response = transport.responseText || "no";
				  switch (response) {
						case 'richtiges passwort':  break;
						
						case "no":					break;
						
						case '3 mal richtig'	 :	alert("Das Passwort war schon 3 mal richtig!");
										  			tasten = '';
													break;
						
						default:	location.href = response;
						
				  }

				},
				onFailure: function(){ alert('Something went wrong...') }
			  });
}