code: public void init(String strDateParam, Date dateTarget, String strLanguage)
      {
          if (strDateParam == null)
              strDateParam = JCalendarPopup.DATE_PARAM;
          dateParam = strDateParam; 
          targetDate = dateTarget;
          languageString = strLanguage;
      }
docs: Creates new CalendarButton.
  @param strDateParam The name of the date property (defaults to "date").
  @param dateTarget The initial date for this button.
  @param strLanguage The language to use.