ERROR: Microsoft JScript runtime error: Object doesn't support this property or method

i am using WCF service to pull the data and its very simple for the purpose of test and it does returning me the data from wcf service but it fails on json2.js on line number 314-316

// We split the first stage into 4 regexp operations in order to work around
// crippling inefficiencies in IE's and Safari's regexp engines. First we
// replace all backslash pairs with '@' (a non-JSON character). Second, we
// replace all simple value tokens with ']' characters. Third, we delete all
// open brackets that follow a colon or comma or that begin the text. Finally,
// we look to see that the remaining characters are only whitespace or ']' or
// ',' or ':' or '{' or '}'. If that is so, then the text is safe for eval.

                if (/^[\],:{}\s]*$/.test(text.replace(/\\["\\\/bfnrtu]/g, '@').
replace(/"[^"\\\n\r]*"|true|false|null|-?\d+(?:\.\d*)?(?:[eE][+\-]?\d+)?/g, ']').
replace(/(?:^|:|,)(?:\s*\[)+/g, ''))) {

here is what i am doing

function serviceProxy(wjOrderServiceURL) {
    var _I = this;
    this.ServiceURL = wjOrderServiceURL;

    // *** Call a wrapped object
    this.invoke = function (options) {

        // Default settings
        var settings = {
            serviceMethod: '',
            data: null,
            callback: null,
            error: null,
            type: "POST",
            processData: false,
            contentType: "application/json", 
            dataType: "text",
            bare: false
        };

        if (options) {
            $.extend(settings, options);
        }




 function GetFederalHolidays() {

        $("#dContacts1").empty().html('Searching for Active Contacts...');  
        ContactServiceProxy.invoke({ serviceMethod: "Holidays",
            callback: function (response) {
    //           ProcessActiveContacts1(response);
                debugger
            },
            error: function (xhr, errorMsg, thrown) {
                postErrorAndUnBlockUI(xhr, errorMsg, thrown);
            }
        });        
}

any help what iam doing wrong? i try to change from dataType: text to json but i get the same error above.