oracle使用utl_http的问题

declare
  soap_request varchar2(30000);
  soap_respond varchar2(30000);
  http_req utl_http.req;
  http_resp utl_http.resp;

BEGIN
  soap_request:= ' <?xml version="1.0" encoding="utf-8"?>
  <soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"  xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:tns="http://service.common.rxn.dbs.com">
  <soap:Body>
    <tns:retrieveFAX>
      <tns:umeroId>f001 </tns:umeroId>
    </tns:retrieveFAX>
  </soap:Body>
  </soap:Envelope>';
 
  http_req:= utl_http.begin_request( 'http://XXXXXXXXXXXX:8080/ipe/services/retrieveFaxService' , 'POST' , 'HTTP/1.1');
       
  utl_http.set_header(http_req, 'Content-Type', 'text/xml; charset=utf-8');
  utl_http.set_header(http_req, 'Content-Length', length(soap_request));
  utl_http.set_header(http_req, 'SOAPAction', 'urn:receiveFAX');
  utl_http.write_text(http_req, soap_request);
  http_resp:= utl_http.get_response(http_req);
  utl_http.read_t