arre yaar all brokers allow short selling intraday. 5paisa, indiabulls, icici i have personally done it. it doesnt make sense not to allow it, even ur regular old fashoned broker allows it intraday. icici squares ur poisiton off at 2:45 or so, indiabulls at 3:10 and 5paisa does not do it even by eod so if u forget to square it off, you will get a short delivery notice and shares will be bought in auction 3 days later. this is bad in some cases, but good if u deliberately wanna be short in a stock till right before market closes.
as far as shorting for more than intraday is concerned, india does not have stock borrowing and lending mechanism in place beacuse of sebi, so that is not allowed, even though i read today that sebi is starting it very soon.