Ajax.resquest Language text is not handling in IE

Hi,

 this is my code 

function Answer_Selected(queryString, questionID, formName, columnName) {
var FormElements = getFormElements1($('form1'));
FormElements += "SourceQuestionID|" + questionID;
var baseUrl = 'SetFormValue.aspx';
var url = baseUrl + "?SourceQuestionID=" + questionID + "&" + FormElements;
new Ajax.Request( url,{
type: 'GET',
cache: false,
contentType: "application/xml; charset=utf-8",
dataType: "xml",
onSuccess: function (transport) {
var Totalresult = transport.responseText;
var resultList = Totalresult.split('^');
for (i = 0; i < resultList.length; i++) {
var result = resultList[i];
var qid = result.substring(0, result.indexOf("|"));
var Value = result.substring(result.indexOf("|") + 1, result.length);
$(qid).value = Value;
}
}
});
}

..bellow is my c# code 

string Params = Request.QueryString["Params"];

.From Ui a dropdown value is comming as Kyllä but in c# i am getting that as Kyll�

So please help me what to do?????????????

Its urgent