This is actually much easier than any of the guides I found online make out.
Firstly, install Eclipse from the repositories. Then open it up, select your default workspace (if you havent already) and then:
- From the Help menu, select “Install new software”.
- Click the “Add” button and add the following:
- Name: Eclipse Updates (Galileo)
- Location: http://download.eclipse.org/releases/galileo/
- Apply your changes and wait for the contents to download.
- When all is ready, select your new source from the drop down and look for the “Programming languages” section.
- Open it up and add the “PHP Development Tools (PDT) SDK Feature”.
- Step through using Next and Finish etc, and after a few moments downloading and installing you now have a PHP ready IDE.