Node.js/Passport/Connect-Filter: Issue during refactoring

I am developing a web application with node.js and I am using passport(http://passportjs.org/) for authentication. I put all the passport code into the app.js file and it works pretty good... During some refactoring steps I decided to put all the passport code into an own file/module called authentication.js and here is my problem:

In app.js there is the following "middleware" code:

app.configure(function(){
   ...
   app.use(passport.initialize());
   app.use(passport.session());
}

which I would like to replace by something like that:

var auth = require('./authentication.js');
app.configure(function(){
   ...
   app.use(auth.initialize(app));
}

But actually I have no idea how the auth.initialize should look like.

I tried something like that:

function initialize(app){
   return function(res,req,next){
      app.use(passport.initialize(res,req, next));
      app.use(passport.session(res,req, next));
      next();
}

but without success... :-(

Does anyone have any idea on this issue?

Thanks in advance...

How about this?

// app.js
var auth = require('./authentication.js');
app.configure(function(){
   ...
   auth.initialize(app);
});

// authentication.js
module.exports.initialize = function(app) {
  app.use(passport.initialize());
  app.use(passport.session());
};

Do make sure that other middleware that Passport depends on, like express.session and express.cookieParser, is configured before Passport is.