As a Jew, I feel that I should point something out.
Y'shua (Jesus) was born on the first of Nizan, which falls in late August, early September every year. Never ever has it, nor will it, fall on December 25th, based on the way the Jewish calendar is structured. Jesus was a Jew, who lived in Israel, practiced Jewish things, and lived a Jewish life, therefore, we can assume that his birth really ought to be based on the Jewish calendar, which hasn't changed for thousands of years.
Feion