problem in getting value of the object attribute in flex

i have an xml which contains 'interface' sub tag, iam converting xml to object using SampleXmlDecoder. compiler did not allow me to access the value of the 'inteface' attrible of the resultobject.

var xml:XML = event.result as XML;
var xmlDoc : XMLDocument = new XML开发者_开发百科Document(xml.toString());
var decoder : SimpleXMLDecoder = new SimpleXMLDecoder(true)
var resultObj : Object = decoder.decodeXML(xmlDoc);
var o:Object = new Object();
o.someprop = resultObj.maintag.item.interface;  

its treating interface as keyword. can anyone tell me the solution for this. Thanks in advance

o.someprop = resultObj.maintag.item["interface"];