stisni na link u prvome koraku i onda stisni save i nemoj odma select stiskat nego namisti all fiels i dodaj u nastavku .ipsw, evo ti na slici
all fiels: http://img710.imageshack.us/img710/4925/allfiels.png
.ipsw: http://img713.imageshack.us/img713/1052/ipsw.png