Is there any way to use another sim on a MC 3GS iPhone?

[Alvi]

Hi, guys I've been making some hard research on this topic of unlocking and jailbreaking MC 3.1.3 3GS

i heard it's possible to downgrade a MC 3GS to 3.1.2 with iTunes 8.2.1 but i just failed, however i heard about those additions to sim cards that allow other carriers to use it, what's they're name and do they really work?

Does anyone know when the new version of OS 3 will come out?

 

[Applejuiced]

Not possible to downgrade unless you got your shsh's saved.
And definatelly no on the unlock once updated to 3.1.3

 

[Alvi]

Not possible to downgrade unless you got your shsh's saved.
And definatelly no on the unlock once updated to 3.1.3

Damn, but will it be possible once 3.1.4 or something comes out?

 

[Applejuiced]

Maybe, we just gotta wait and see.

 

[labman]

Since it not out yet!

Damn, but will it be possible once 3.1.4 or something comes out?

How would anybody be able to answer this?