InfoPath Dev

My InfoPath form contain a Data Connection to a SharePoint web service:

http://<MyServer>/_vti_bin/UserProfileService.asmx?WSDL

In my code (in the OnLoad event) I try to operate this Data Connection by this code:

function XDocument::OnLoad(eventObj)

{

var objNetwork = new ActiveXObject("WScript.network");

var currentLogin=objNetwork.UserDomain+"\\" +objNetwork.UserName ;

if(XDocument.IsNew) {

var dataObj=XDocument.DataObjects("GetUserProfileByName");

var dataDom=dataObj.DOM;

dataDom.setProperty("SelectionNamespaces", 'xmlns:dfs=http://schemas.microsoft.com/office/infopath/2003/dataFormSolution xmlns:d="http://schemas.microsoft.com/office/infopath/2003/ado/dataFields" ' );

dataDom.selectSingleNode ("/dfs:myFields/dfs:queryFields/s0:GetUserProfileByName/s0:AccountName").text=currentLogin ;

dataObj.Query();

} 

}

I try to put "currentLogin" as parameter of the web service, But I get error that:

Reference to undeclared namespace prefix:'s0' .

When I watch the field's tree of this Data Connection (named "GetUserProfileByName") in the Data Source view I have:

MyFields -> queryFields -> s0:GetUserProfileByName -> AccountName.

What is the problem in my code???

The problem lies in this line:

dataDom.setProperty("SelectionNamespaces", 'xmlns:dfs=http://schemas.microsoft.com/office/infopath/2003/dataFormSolution xmlns:d="http://schemas.microsoft.com/office/infopath/2003/ado/dataFields" ' );

You never set the s0 namespace.