//reqEnv.declareNamespace("http://schemas.xmlsoap.org/wsdl/", "wsdl");
reqEnv.declareNamespace("http://www.w3.org/2001/XMLSchema-instance","xsi");
OMElement operation = omfactory.createOMElement("echoDate", "http://soapinterop.org/", null);
SOAPBody body = omfactory.createSOAPBody(reqEnv);
body.addChild(operation);
operation.addAttribute("soapenv:encodingStyle", "http://www.w3.org/2003/05/soap-encoding", null);
OMElement part = omfactory.createOMElement("inputDate", "", null);
part.addAttribute("xsi:type", "xsd:dateTime", null);
part.addChild(omfactory.createText("2002-07-18T19:40:30.387-06:00"));