Posting to Facebook in PHP

We are looking for a simple script in PHP that will post a comment to our Facebook account. It should take as input the text string to be posted, as well as whatever identifying information is required to authenticate to Facebook (username? password? special tokens?). It should return a value indicating success or failure. The programmer will be expected to set up a dummy Facebook account to test the routine, and to provide us with explicit instructions on how to establish the proper authentication with our own Facebook account. We are running PHP version 5.2.17.