XMLHttpRequest.prototype.sendAsBinary = function(datastr) {
    function byteValue(x) {
        return x.charCodeAt(0) & 0xff;
    }
    var ords = Array.prototype.map.call(datastr, byteValue);
    var ui8a = new Uint8Array(ords);
    this.send(ui8a.buffer);
}

http://javascript0.org/wiki/Portable_sendAsBinary

Use this to enhance non firefox browsers to support the sendAsBinary method.

Portable sendAsBinary for XHR

html5

JavaScript