set test cookie and return beacon gif

cookietest.js

var http = require('http');
var imgdata = [
    0x47, 0x49, 0x46, 0x38, 0x39, 0x61, 0x01, 0x00, 0x01,
    0x00, 0x80, 0x00, 0x00, 0xFF, 0xFF, 0xFF, 0x00, 0x00,
    0x00, 0x21, 0xf9, 0x04, 0x04, 0x00, 0x00, 0x00, 0x00,
    0x2c, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x01, 0x00,
    0x00, 0x02, 0x02, 0x44, 0x01, 0x00, 0x3b
];
var imgbuf = new Buffer(imgdata);

http.createServer(function(request, response) {
    console.log(request);
    response.writeHead(200, {
        'Content-Type': 'image/gif',
        'Content-Length': imgdata.length,
        'Set-Cookie': ['type=hoge; domain=cookietest.cou929.nu; path=/'],
        'Cache-Control': 'private, no-cache, no-cache="Set-Cookie", proxy-revalidate'
    });
    response.end(imgbuf);
}).listen(5001);