I just want to point out that Jesus doesn't have the monopoly on festivals marking the 'birth of the sun'. All over the world light festivals are held by a number of religions and spiritual thought systems. In fact, Jesus wasn't born on December 25th at all. It was decided by a council of bishops around the mid-300s - a time coinciding with Saturnalia a widely recognized pagan holiday practised throughout the Roman world at the time.

As for Christmas, it is in numerous parts of the world celebrated over a period of two or more weeks (ie. the 12 Days of Christmas). This includes the very old tradition of celebrating the period between Christmas Day and Epiphany two weeks later (celebrating the day the wisemen arrived).