jailbroken 4.2.1 by redsn0w with a 6.15.00 Baseband

Here's what I did:

Jailbroke Iphone via redsn0w

Opened Itunes 9.0.3

Opened mughalG's Iphone Unlocker IPhone Unlocker 4 BB 6.15 [nowifi].rar

Clicked Get it

Reset phone 2 times

and DONE!

For those that not get to work.
=======================
Download ifunbox
connect your iphone and open ifunbox.

click on "Rawfile system"
open VAR
open root
open media

If it is empty..make new folder.named"Cydia"
open Cydia ..
IN "cydia" folder make another folder named:AutoInstall"
IN :AutoInstall" folder past ultrasn0w files(First extrac it then Past)
REboot 2 time..
ENjoy

The ultra sn0w files are here:
ulrasn0w.6.15 by zain.rar - 4shared.com - online file sharing and storage - download


UPdated
Iphone Unlocker NoWifi V 1.1 beta by MughalG
Iphone unlocker [NoWifi] has been updated to support latest Itune versions.

What's New:

* Supports all Itune versions
* Ultrasn0w updated to latest version 1.2.3 to support firmware upto 4.3.3

Download link:

IPhoneUnlocker.rar