in addition to gramps I suggest aside from this question about the calendar widget, that you should have a look to the Adobe widgets at one go. Explanations you will get here:
June 14, 2010 — A new build of Dreamweaver Widget Browser has been released.
Download the Dreamweaver Widget Browser
The Adobe® Dreamweaver® Widget Browser is an Adobe AIR® application
that lets you preview and configure widgets using a visual interface.
Hi, The best one I have is this one:
It makes exactly the calendar your looking for and comes with some preset styles and the most common languages and time and date formats.
That saves you a lot of time. In just a couple of clicks you have it on your web page.