function check_username(url) {
    if (window.XMLHttpRequest) {
        req2 = new XMLHttpRequest;
    } else if (window.ActiveXObject) {
        req2 = new ActiveXObject("Microsoft.XMLHTTP");
    }

    if (req2) {
        req2.open("POST",url, true);
        req2.setRequestHeader('Content-Type','application/x-www-form-urlencoded');
        d= document.signupFrm;
        ele_len = d.elements.length;
//alert(ele_len);
        var postvalues="";
//alert(d.country_id.value);
        postvalues="username="+d.username.value;
//postvalues="countryid=US";
//alert(postvalues);
        req2.send(postvalues);
        req2.onreadystatechange = processReqChange2;
    } else {
       alert("Please use latest version of the current browser to function properly");
       doesNotSupport = false;
    }
}

function processReqChange2() {
    if (req2.readyState == 4) {
        if (req2.status == 200) {
            var aa=req2.responseText;
            document.getElementById('userDiv').innerHTML = aa;
        }
    }
}