src/org/tiefaces/components/websheet/serializable/SerialWorkbook.java
private void writeObject(final java.io.ObjectOutputStream out)
			throws IOException {
		out.defaultWriteObject();
		if (wb != null) {
			wb.write(out);
		}
	}
private void writeObject(final java.io.ObjectOutputStream out)
			throws IOException {
		out.defaultWriteObject();
		if (wb != null) {
			wb.write(out);
		}
	}
save the workbook before serialize.

@param out
outputstream.
@throws IOException
io exception.