There is no denying that the Chor Chor (thiruda thiruda ) (at around 2.40mins) theme was heavily inspired by the Extra Terrestrial theme by John Williams ( starts at 1.40 mins) .
Its a different question that Sun TV blalantly lifted portions of the same track for their theme! I have uploaded as well as attached the file. You guys decide!. http://rapidshare.com/files/88898218/21_-_End_credits_.mp3.html