Does anyone know of a free WYSIWYG PHP editor?

I have a website that has been designed in php format. While there are dozens of html editors, such as Front Page, Dream Weaver, NVU, and so on, the only php editors I've been able to find are text editors. I'm looking for a PHP editor with a graphic interface similar to the HTML editors I'm used to working with so I can manage the site updates myself. Is there any such thing as a freeware php editor with a graphic interface available that you can recommend?