         if (!validateCell(rowIndex, columnIndex))
             return false;
         
-        removeSelection();
-        addCellRegion(rowIndex, columnIndex, 1, 1);
+        internalSetCellRegion(rowIndex, columnIndex, 1, 1);
         
         return true;
     }

    //----------------------------------
    //  selectionLength
    //----------------------------------
        
    /**
     *  If the selectionMode is either <code>GridSelectionMode.SINGLE_ROW</code> or
     *  <code>GridSelectionMode.MULTIPLE_ROWS</code>, returns the number of

    {
        return contains(cellColumnIndex, cellRowIndex);
    }
}
