cf-runtime not working

I'm trying to deploy a nodeJS native app to CF. I'm using cf-runtime module to figure out the real server's IP and port address my app is running on. However with adding the

var cf = require('cf-runtime');
var local_port = 3000;
......
....business code....

 }).listen(local_port);

  console.log('Proxy server running at localhost:' + local_port);
  console.log("host: " + app.host + " port: " + app.port);

I'm seeing an error as below:

Creating Application: OK Uploading Application: Checking for available resources: OK Processing resources: OK Packing application: OK Uploading (44K): OK Push Status: OK Staging Application 'leohu-proxy': OK Starting Application 'leohu-proxy': .......Error: Application 'leohu-proxy's state is undetermined, not enough information available.

thu@geekdev:~$ vmc logs leohu-proxy ====> /logs/staging.log <====

# Logfile created on 2012-10-07 17:41:24 +0000 by logger.rb/25413 Skipping npm support: npm-shrinkwrap.json is not provided

====> /logs/stdout.log <====

Proxy server running at localhost:3000 host: 172.30.49.236 port: 15669

Can anyone exlain why, or advise me what to do here?

A following question might be: can I access this app from another app by using the exposed host and port address?