Mootools 1.3 DatePicker class

I think that DatePicker mootools class by monkeyphysics is fantastic. It is fast, well written, it has a nice layout and some awesome options like the inputOutputFormat one. Recently I upgrade to mootools 1.3 without compatibility in a project of a php framework which uses this class.
So I need to make DatePicker class working with the new release of my favourite js framework.
During the upgrade work I found and fixed a bug in the date selection when selecting a day of the previous/next year in january/december months view.
Moreover I added the z-index management so that the calendar is always shown above all document elements.
Maybe more improvemets will come in the next future.
My project is a fork of the original one and hosted on my github repository.
From command line you may simply clone my project

git clone git://github.com/abidibo/mootools-datepicker.git