Lorna Mitchell has posted the last part of her development process towards creating a sample REST server in PHP:

This is part 3 of my article about writing a restful service server. If you haven't already, you might like to read part 1 (covering the core library and grabbing the information we need from the incoming request) and part 2 (covering the service handler itself) before reading this section. This part covers the Response object that I used to return the data to the user in the correct format.

She show how she created the object to push the response back out to the client with an output() method that displays the XML response in a manually generated format.