Since this is a rumour, no names or places will be mentioned. I will try in the mould of gossip magazines :-).
There was a professor in a college who thought his students dressed indecently (whatever it means). So he railed at them and asked them to dress decently. Golden rule for professors is never to irritate the students. They decided to act smart and the next day all the guys came dressed in dhoti and the girls in saree. It was mockery of the highest order of the professor.
But the students of many years later were to pay the price when the same professor became the head of a university. He decided to get even and declared a dress code that encompassed all colleges under the university. So now you know the insider info of a dress code in a university decreed by a professor.
Can anybody confirm this?
Update: The rumour is unsubstantiated, I believe.