how to create session express.js

I run localhost:3000/name/john, create a cookie then localhost:3000/name to display the cookie I have a console error "TypeError: Can not read property 'name' of undefined"

look my code

 var express = require('express')
     , http = require('http') 
     , path = require('path') ;

var app = express();        

        app.configure(function(){
            app.set('port', process.env.PORT || 3000);
            app.use(express.bodyParser()) ;
            app.use(express.methodOverride()) ;
            app.use(app.router);

            app.use(express.cookieParser());  
            app.use(express.session({ secret: 'secret'}));
        }) ;

      app.get('/name/:name', function(req, res){
            res.cookie('name' , req.params.name).send('<p>the cookie <a href="/name">Go here</a></p>') ;
       });

      app.get('/name', function(req, res){
          console.log(req.cookies.name);
          res.send("index");
      });  

    http.createServer(app).listen(app.get('port'), function(){
      console.log('Express server listening on port ' + app.get('port'));
    });

how to solve this problem ? thanks