This option show/hide the calendar grid by setting the property CalendarComponent.SHOW_GRID to true/false.
The calendar grid is painted using the CalendarSkin.GRID_COLOR on the space between rows and colors. The spacing between rows is set using the CalendarComponent.INTER_ROWS_SPACING. The spacing between columns is set using the CalendarComponent.INTER_COLUMNS_SPACING. If CalendarComponent.INTER_ROWS_SPACING is 0 and CalendarComponent.INTER_COLUMNS_SPACING is 0 then the grid will no longer be displayed even if CalendarComponent.SHOW_GRID is true because there is no space where the grid should be painted.
The code below shows how to show/hide the grid: 
<CODE>
CalendarComponent calendarComponent = new CalendarComponent();
//    show grid
calendarComponent.setCalendarProperty(CalendarComponent.SHOW_GRID, new Boolean(true));
//    hide grid
calendarComponent.setCalendarProperty(CalendarComponent.SHOW_GRID, new Boolean(false));
</CODE>