PHP UML Modeller and generate code

Back in my old uni days I used Rational Rose which was great, I could do my UML diagrams, and generate my code for Java.

Ive just started with PHP OOP, and decided to look for a package that would allow me to do my class diagrams and generate the code for PHP, but cant belive how hard it is.

I would prefer  the software to be free for personal user, so tried:-

Through work I have Microsoft Visio, but it doesn't have PHP code generation built in

What do other people use to develop their diagrams, or is it just easier to do what Im doing at the moment, and code from the diagrams instead of it being automatic.

Thank you