Hi Kusup,
XAMPP is a decent Apache/PHP/MySQL setup, so there's no reason it
shouldn't work.
Using SabreDAV you can create a CalDAV server, and create custom
backends for yourself.
The existing backends are minimal, and serve as a starting point for
integration into your own infrastructure.
Here's 2 starting points that could be useful:
http://code.google.com/p/sabredav/wiki/CalDAV
http://code.google.com/p/sabredav/wiki/CalDAVIntegrationGuide
I'd suggest just starting off with the detault CalDAV server and swap
out components for your own as you develop it further.
Good luck,
Evert