NodeJS: Integrate with PHP

I've heared that NodeJS is great for making real-time chat applications and I want to implement a chat on my website. Right now I only have the design so I have to make the back-end code now.

However when I'm using socket.io + express it doesn't work out like it should.

Code from server.js:

var app = require('express')();
var http = require('http').Server(app);

app.get('/', function(req, res){
res.sendFile(__dirname + '/index.php');
});

http.listen(3000, function(){
 console.log('listening on *:3000');
});

I simply want to show index.php on localhost:3000, however when I browse to the website it doesn't want to show the page. Instead it downloads the index.php file.

But... If I change the extention of the file to html, so index.html it works. But that is not what I want.

I know there are some smart guys out there that can solve this problem in no time. I've been sitting for a very long time myself trying to sovle it.

The website

via Nabil Hayek