function loadCalendar() {
        
        var calHandler = {
            onSelect : function(date) {
                alert('Date sélectionnée');
                // Suite des traitements...
            }
        }
        
        var params = {
              
        }
        
      dp_cal  = new calendar('epoch_popup1', 'popup', document.getElementById('date_dep'), params);
      dp_ret  = new calendar('epoch_popup2', 'popup', document.getElementById('date_arr'), params);

    }
   addEvent(window, 'load', loadCalendar, false);