Simple small program, the idea came to me when I visited a blog (which I don't remember ...), there was a calendar, but when we changed the date (specifically of months), whole page was recharged ... (There, there isn't this problem more ...)
Software in pictures :
there is still the disadvantage of loading time of the applet ...
Today, this kind of tool is a bit "dated" since many libraries (jQuery, Yahoo User Interface, ...) provide this kind of calendar in Javascript.
Following example, the JQuery date widget:
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