Web Debugging Environment for PHP?

Sarek asks: "I work in a mostly Windows environment at work writing ASP but I much prefer PHP. While I seem to have convinced the powers that be that PHP is better, there is only one hurdle I can't seem to overcome to get them to start writing in PHP. I can't seem to find a debugging environment for PHP like there is for ASP. While I'm perfectly happy writing without it I have seen a great many benefits to having one, such as faster debugging. Has anyone thought to make one yet? And if so where can I find it? For those of you that don't know ASP uses MS InterDev. Which in short allows you to debug ASP just like you would debug a compiled language, by setting breakpoints, stepping through the code, etc..."