Before you totally run out of battery dial **21*PHONE NUMBER OF THE PERSON YOU WANT TO RECEIVE YOUR CALLS FROM#SEND
From then if somebody call you it will ring on the person's phone you have put. Cancel it any time from your own SIM card by dialing ##21#SEND.Remember if you don't have battery on your phone at all you can also remove your SIM card and put it into another person's phone then put the code. In any case always dial ##21#SEND from your own SIM card to cancel it.