Illegal lo.. If legal, then all water set phones can become AP set lo.. But as i know, many AP shops doing this lo.. Another example is that half year ago, i brought my bro to buy a new phone at kotaraya plaza(my bro want used s700i since no more new one and i saw few in kotaraya plaza) then i heard the junior seller there took the traded in k700i and asked the senior "make it become new set ar?" they the senior seller replied "yaya do it now" OMG! They did their conversation just infront of me and my bro... So, the phone u using right now might be used phone ooooooooo... Mine wont, cuz ori set

edit:typo