code: function(cal) {
          var date = YAHOO.widget.DateMath.getDate(this.getYear() - cal.cfg.getProperty("YEAR_OFFSET"), this.getMonth(), 1);
          cal.cfg.setProperty("pagedate", date);
          cal.render();
      }
docs: Updates the Calendar rendered state, based on the state of the CalendarNavigator
  @method _update
  @param cal The Calendar instance to update
  @protected