Admin Framework? (Before recreating the wheel)

[Demonic]

All/most systems require a administration panel and before I recreate the wheel or atempt at it I was wondering if there was a framework that has the following.

 

-Authentication System

-Create pages on the go (so I can create admin modules for doing certain administration tasks)

 

I want to be able to use a system with in my own html so it's easy to implement in any app I create (some form of template system).

 

Not that demanding but something along them lines and simplicity for helping creating admin pages easy/fast/quick/lightweight and easy to extend or modify (source is easy to read).  Which supports mysql for database storage.