Webservice return string ???? after invoked

Hi,

After i invoke webservice (suds) with some paramerter in thai language then resault show "??????"

This is my code :

function test(){
 
    var callparams = {
        str: '????????', //<<----   Thai language
       };
 
var suds = new SudsClient({
         endpoint: Titanium.App.Properties.getString('services'),      
         targetNamespace: 'http://tempuri.org/'
});
 
try{
       // TestString Function will return str in xml 
       suds.invoke('TestString', callparams, function(xmlDoc) {
       var results = xmlDoc.documentElement.getElementsByTagName('TestStringResult');
 
       if (results) {
         // Value should be '????????'
         Ti.API.info('message',results.item(0).text); // Resault is "????????????"
 
      } else {
 
            }
      });
 
   } 
   catch(e) {
 
    }
 
}

pongpang