Passare variabili GET senza ricaricare la pagina php

[artorius]

meglio ancora:

function updateCalendar(anno, mese)
{
   new Ajax('inc/calendario.php', {method: 'get', data : {'aa' : anno, 'mm': mese}, onComplete : function(obj)
      {
          $('CalendarWrapper').setHTML(obj);
          $('PrevMonth').observe('click', prevMonth);
          $('NextMonth').observe('click', nextMonth);
      }
   });
} 

poi

var currentMonth, currentYear;
window.addEvent('load', function(){
   currentMonth = <?=$_GET['mm'] ? $_GET['mm'] : 'null'?>;
   currentYear = <?=$_GET['aa'] ? $_GET['aa'] : 'null'?>;
   if(!currentMonth || !currentYear)
   {
      var d = new Date();
      currentMonth = !currentMonth ? d.getMonth() + 1 : currentMonth;
      currentYear = !currentYear ? d.getFullYear() : currentYear;
   }

   updateCalendar(currentMonth, currentYear);
})

Le altre vanno bene