code: function(id) {
          var date = this.getDateFieldsByCellId(id);
          return (date) ? DateMath.getDate(date[0],date[1]-1,date[2]) : null;
      }
docs: Retrieves the Date object for the specified Calendar cell
  @method getDateByCellId
  @param {String} id The id of the cell
  @return {Date} The Date object for the specified Calendar cell