Requirements:

• Modified version of Pwnage Tool and iOS4 Jailbreaker ( Here )
• Firmware 4.1 for iPhone 3GS ( Here )
• If you are jailbroken in Firmware 3.1.2 or 3.1.3 using Spirit, you need to install the package Spirit2pwn in Cydia. (repo :http://repo.woowiz.net)
• iTunes 10 installed on your Mac
• iPhone 3GS old Boot only.

 

Guide:

1. Launch PwnageTool and connect your iPhone via USB. This opens a pop-up with copyright, click OK and begin.
 

2. Click the Advanced Mode button and then select the iPhone 3G. Finally, click on the blue arrow to continue.
3. Then will begin the search for the original 4.1 firmware inside your computer. If you have more firmware stored in the Mac, be sure to select the one corresponding to the 4.1 version, then click on the arrow to continue.
 
4. At this point, click on "Global" and begin the customization:
 

• This version of PwnageTool does NOT permit you to activate your iPhone, you NEED an original SIM card

Adjust the partition size (or leave as is) and continue.
 
5. Through this screen, you can add repositories in Cydia and then install all the applications you want, so that when you put custom firmware on the iPhone it's already full of applications. Enter the section "Manage Sources" and add the repositories you want. Mine is: http://cydia.myrepospace.com/HackStor/, but others found in our Sources . Add To Queue. Now enter into the "Download Package, refresh and select the applications you want to install, then click Add To Queue. Will all be displayed in the "Package Selection", make sure everything is correct and click the blue arrow to continue. Obviously, this step is optional, you can continue without adding any packages.
 
6. Remove the two cue from "Logo Ignition" and "Restore logo, so you have the original Apple or click on" Search "to replace the images, then keep clicking on the blue arrow
 
8. It will create the custom firmware, you will be prompted for the password of the system. Do not insert and run the application iOS4.1 Jailbreaker, click on "Continue" twice in a row and enter the administrator password if required.
 
9. After entering the password, wait for the end of the process and reopen Pwnage Tool by entering the password again. At this point you will get a kitten and a pop up where you read the words: Close PwnageTool put the phone in recovery mode and restore using iTunes. Actually I tried to restore the iPhone on, without even the Recovery Mode and iTunes has it own mandate, so save a step.
10. To restore click the ALT key (Options) on your keyboard and mouse simultaneously with the Restore button in iTunes.
11. This opens a small window from which you select the custom 4.1 firmware you've just created. iTunes will begin to extract, verify, and restore your iPhone 3GS
 
We're almost there! Now you have an iPhone 3GS updated to firmware 4.1, and more is jailbroken with Cydia installed.

• If the iPhone will come on when you will notice Cydia icon in white with no repository. Launch the application, which came into Manage> Sources> Edit> Add and add :

• If you found the problem causing the crash Mobile Safari startup, you must add the following repository and install Safarifix:

    http://repo.woowiz.net http://repo.woowiz.net