ExpressJs sessions not working on IE / server

IE explorer is not recognizing cookies/sessions on a server (code works on localhost)

Session setup:

app.configure(function () {
    app.use(express.cookieParser());

    app.use(express.session({
        secret: 'secret',
        fingerprint: function(){ return ''; }
    }));

    app.use(app.router);

});

Testing sessions:

app.get('/session_get', function(req,res){    
    console.log (req.session);
    res.render("session",{
        user : req.session.user_name,
        userId : req.session.user_id,
        dt: req.session.dt
    });
}); 
app.get('/session_set', function(req,res){
    req.session.user_id = 1;
    req.session.user_name = "RG";
    req.session.admin = 1;
    req.session.dt = new Date();
    res.end();

});

browsing to /session_get sets the session, and /session_get displays the session variables.

It works fine on localhost, but on several remote servers (nodejitsu / appfog) the /session_get is always responding empty. Both on render (jade) as well as using console.log

I tried several suggestions, including one about fingerprint and cookies being modifed on IE (TJ Holowaychuk) but nothing.

using "express": "~3.0.4"