wow … just spent another 2 days trying to figure out how to:
jailbreak my 3gs from OS 3.0.1 to 3.1.2 and while keeping baseband 4 on my mac.
[now … i’ve gone through some troubles to make sure, my 3GS is made before week 40 (aka old baseband 4, 4 & 5th number on your serial) and have not updated to 3.1, not to lose my tethering via carrier 6 file :) ]

“what had happened was”:

1 – followed this guide on macbook pro (aluminum, snow leopard), itunes 9.1 (most likely this was a root of my problems), pwnage

2 – got error 1600 / stuck in DFU – nothing works, tried:
DFU: 30 sec power + home,  YT vids – can’t get out
1600 (1604, etc): restore mode, different USB ports, windows iREF (works on 3g only, have not tried “fix recovery mode loop”), then sn0wbreeze & it told me “detected … can’t be jailbreaked …”

3 – tried old white macbook w/
– itunes 8 and 9.0.1
– delete directory trick (~user/library/itunes/device support – delete content before you run pwnage tool ) … still didn’t work, but later i’ve figured out i was using the firmware cooked on macbook pro, snow …

…. next day. created a clean mac os login
4 – what finally worked: white old macbook w/ leopard (not snow), itunes 9.0.1, pwnd 3.1.5, restore 3.1.2

to get out of DFUblackra1n (THX! making donation now) – got my phone back! (but because was 3.0.1 it didn’t jailbreak it)

re created 3.1.2 restore file w/ activation (carrier – yes, if you have att) on pwnage tool 3.1.5. made sure “…/device support” dir is empty before i started cooking & it went trough! (phone still not plugged in at this point)
– restored on iTunes 9.0.1, white, old macbook w/ just leopard on it & a clean account
– once restore & backup (2h later) … cydia said “you phone’s SHSH … 3.1.3 has been backup up” so i got my SHSH … i think (umbrella didn’t work for me, even with ECI nubmer).
…. so it WORKED


if you can do without jailbreak on 3GS OS 3.0 … consider … not having your phone avail for next few days :)

if you already have 3GS OS 3.1 + just blackra1n it … it will take 10 sec! :) – there’s a way to get your SHSH after via umbrella (windows, ih8sn0w) … but it didn’t work for me.

BEFORE you start:
– get your serial, carrier, OS, baseband firmware & ECID numbers
– search google for how to with exactly those numbers (eg. “jailbreak 3g os 3.1 3.1.3 mac”)
– don’t user snow leopard, use iTunes 9.0.1