I still have 3.1.3 and never upgraded. How do I unlock this with Mac? Do I need to upgrade my firmware? Which version of pwnagetool do i use? I tried 3.1.5 as per instructions on this page and restore to iPhone2,1_3.1.3_7E18_Restore.ipsw and it said "SRY I HAZ FAIL!!1" please help me, i don't want zune!