* @param exportValues the export values
     * @param displayValues the display values
     * @return <CODE>true</CODE> if the operation succeeded, <CODE>false</CODE> otherwise
     */
    public boolean setListOption(String fieldName, String[] exportValues, String[] displayValues) {
        if (exportValues == null && displayValues == null)
            return false;
        if (exportValues != null && displayValues != null && exportValues.length != displayValues.length)
            throw new IllegalArgumentException(MessageLocalization.getComposedMessage("the.export.and.the.display.array.must.have.the.same.size"));
        int ftype = getFieldType(fieldName);
        if (ftype != FIELD_TYPE_COMBO && ftype != FIELD_TYPE_LIST)
            return false;
        Item fd = fields.get(fieldName);
        String[] sing = null;
        if (exportValues == null && displayValues != null)
            sing = displayValues;
        else if (exportValues != null && displayValues == null)
            sing = exportValues;
        PdfArray opt = new PdfArray();
        if (sing != null) {
            for (int k = 0; k < sing.length; ++k)
                opt.add(new PdfString(sing[k], PdfObject.TEXT_UNICODE));
        }
        else {
            for (int k = 0; k < exportValues.length; ++k) {
                PdfArray a = new PdfArray();
                a.add(new PdfString(exportValues[k], PdfObject.TEXT_UNICODE));
                a.add(new PdfString(displayValues[k], PdfObject.TEXT_UNICODE));
                opt.add(a);
            }
        }
        fd.writeToAll( PdfName.OPT, opt, Item.WRITE_VALUE | Item.WRITE_MERGED );
        return true;
    }