Bouncy not works with subdomains

I'm using Bouncy on my server. But it not works with subdomains.

My script:

var bouncy = require('bouncy');

var server = bouncy(function (req, res, bounce) {
    if (req.headers.host === 'www.example.com') {
        bounce(8001);

    } else if (req.headers.host === 'sub.example.com') {
        bounce(8002);

    } else {
        res.statusCode = 404;
        res.end('no such host');
    }
});
server.listen(80);

When I visit www.example.com I see my page. But when I visit sub.example.com Forever throw me error

error: Forever detected script was killed by signal: SIGKILL
error: Script restart attempt #1

Who knows how to solve this issue?