code: @Override
      public Response sendSMS(String CorpNum, MgtKeyType KeyType, String MgtKey,
                              String Sender, String Receiver, String Contents)
              throws PopbillException {
          return sendSMS(CorpNum, KeyType, MgtKey, Sender, Receiver, Contents,
                  null);
      }
docs: /* (non-Javadoc)
  @see com.popbill.api.TaxinvoiceService#sendSMS(java.lang.String, com.popbill.api.taxinvoice.MgtKeyType, java.lang.String, java.lang.String, java.lang.String, java.lang.String)