/**
   * Returns CSR File with a given serial number
   *
   * @return CSR File Serial Number
   * @throws AxisFault
   */
  public CsrDTO getCSRFromSerialNo(String serialNo) throws AxisFault {

    try {
      return stub.getCsr(serialNo);
    } catch (Exception e) {
      String message = e.getMessage();
      handleException(e.getMessage(), e);
    }
    return null;
  }