InfoPath Dev

Hi..

 I'm need to get a especific value from a secondary data soruce but infopath send this error,

The following error occurred:

'null' es nulo o no es un objeto
File:script.js
Line:34
 

this is the code

var domSimbols = XDocument.GetDOM("Simbolos");

var domSimbols = XDocument.GetDOM("Simbolos").setProperty("SelectionNamespaces", 'xmlns:ds1="http://schemas.microsoft.com/office/infopath/2003/myXSD/2008-02-12T23:14:55"');

var domSimbols = XDocument.GetDOM("Simbolos");

// Source nodes.

var oSimbols = domSimbols.selectNodes("/ds1:myFields/ds1:dataFields/ds1:Simbolos");

var sdd = oSimbols.nextNode()

var rr = sdd.selectSingleNode("/ds1:Proceso").nodeValue                        ///  this is the line 34

XDocument.UI.Alert(rr);  

Regards,

is Proceso a field? what type?  It may be your xpath syntax.