Writing a node application and encountering an error when running 'node server.js'

I'm writing a node application and I recently switched from port 3000 to port 80 on my Mac Os X Lion machine (running 10.7.4) and whenever I run node server.js I get the following error

events.js:66
    throw arguments[1]; // Unhandled 'error' event
                   ^
Error: listen EACCES
    at errnoException (net.js:768:11)
    at HTTPServer.Server._listen2 (net.js:891:19)
    at listen (net.js:935:10)
    at HTTPServer.Server.listen (net.js:984:5)
    at Object.<anonymous> (/Users/ajain/Documents/Projects/Time-Feed/server.js:127:5)
    at Module._compile (module.js:449:26)
    at Object.Module._extensions..js (module.js:467:10)
    at Module.load (module.js:356:32)
    at Function.Module._load (module.js:312:12)
    at Module.runMain (module.js:492:10)

Any idea on what I have to do to fix the issue?

You need to have the root privilege in order to listen on a port number below 1024. Therefore, you may use the sudo command.

sudo node server.js

If sudo didn't help just change the port to something like 1234 or maybe 2000 or 3000.