code: @Override
  	public Response sendSMS(String CorpNum, String MgtKey, String Sender,
  			String Receiver, String Contents)
  			throws PopbillException {
  		if (MgtKey == null || MgtKey.isEmpty())
  			throw new PopbillException(-99999999, "관리번호가 입력되지 않았습니다.");
  
  		return sendSMS(CorpNum, MgtKey, Sender, Receiver, Contents, null);
  	}
docs: /* (non-Javadoc)
  @see com.popbill.api.CashbillService#sendSMS(java.lang.String, java.lang.String, java.lang.String, java.lang.String, java.lang.String)