How to Unlock 1.1.4 and Downgrade to 3.9-fakeblank iPhone Bootloader (Mac)
These are instructions on how to downgrade to the 3.9-fakeblank Bootloader and unlock 1.1.4 using iPlus 2.0b for Mac.
iPlus 2.0b Features
1-Unlock and if required automatically downgrade the bootloader to 3.9FakeBlank
5-Add the following packages: Installer, Community Services, BSD subsystem, OpenSSH, VT-100
Plus: BSD Fix, VT100 Fix, Summerboard themes directory fix, Relocates Fonts and Ringtones (More than 120MB free)
Before attempting this make sure you have restored your iPhone to 1.1.4 using iTunes.
Download iPlus 2.0b from here.
From the file we just downloaded extract the iPlus2.0 folder to your Desktop.
Launch Terminal by selecting it from your Applications:Utilities folder
Enter the following command into your Terminal window then press Enter
Enter the following command into the Terminal window to unlock and downgrade your bootloader.
NOTE**: This command will automatically activate, jailbreak, and unlock. If necessary and able it will also change your bootloader to the 3.9-fakeblank Bootloader. If you don't want to unlock just drop the -u and iPlus will only activate and jailbreak!
The program will then put your iPhone into recovery mode. Once it is successfully in recovery mode you will be asked to wait 2 minutes and 30 seconds.
Once rebooted it will tell you that Jailbreak and setup for next pass completed. Now it will proceed to unlock, downgrade and activate.
Once your iPhone comes out of its final reboot it will be activated, jailbroken, unlocked and bootloader downgraded !!!!
THANKS***: A big thanks go to aviegas for creating iPlus!!!