Project management software that will allow me to plan classes and functions

I'm working on a big PHP web-project and I was wondering - Is there any Project Manager software that will allow me to plan the "skeleton" of the project - meaning the classes, input & expected output of fu开发者_StackOverflownctions and things like that?

Thanks in advance, Daniel.

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you can use UML to define classes.

There is a good free software called starURL.

http://staruml.sourceforge.net/en/

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I've used Umbrello in the past. Pretty nice and open source :)

http://uml.sourceforge.net/

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Enterprise Architect from Sparx Systems is native on Windows, can do PHP forward and reverse engineering, and has a whole bunch of functionality around project planning and tracking where you mark model elements as Proposed, Implemented, etc, and create tasks and things.

I haven't played around much with either, though, I just know it's there. Also, EA is a commercial product if that's an issue.