iCallID = webServiceCallerBody.echo.callService(
  handleResult, "echoString", "Asynchronous Call");

function handleResult(res) {
  if (!res.error) {
    alert("Successful call. Result is " + res.value);
  }
  else {
    alert("Unsuccessful call. Error is " + res.errorDetail.string);
  }
}

function callSynch() {
  var co = webServiceCallerBody.createCallOptions();
  co.funcName = "echoString";
  co.async = false;
  var oResult = webServiceCallerBody.echo.callService(co, "Synchronous Call");
  handleResult(oResult);
}

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