node.js + express.js: session handling with mongodb/mongoose

Right now i'm storing my session data in the "memory store" which comes bundled with connect(express). But I want/have to change this for production.

The application is using mongodb and I installed mongoose to handle all db-communications.

e.g. Connect to the DB after initializing my app:

var mongo = require('mongoose');
mongo.connect('mongodb://localhost/myDb');
mongo.connection.on('open', function () {
  app.listen(3000);
}

I found the connect-mongodb module, but I don't know how to implement it using mongoose, or if it's actually possible? I need to add something like this:

var mongoStore = require('connect-mongodb');
// ...
app.use(express.session({
  secret: 'topsecret',
  maxAge: new Date(Date.now() + 3600000),
  store: new mongoStore({ db: 'myDb' })
}));

or do I have to define my db connection a second time using the mongodb-module directly?