Jailbreak and update your iPhone 3gs to iOS 6.1.2.

I know this isn't a sport related topic, however I wanted to share these instructions with those that need it!

It helped me resolve the "No Service" on my kids iPhone 3GS

Appreciate if you leave a quick comment if it worked...

Try to find and download the following required files:
iPhone2,1_6.1.2_10B146_Restore.ipsw
iPhone2,1_6.0_10A403_Restore.ipsw
redsn0w_win_0.9.15b3
evasi0n 1.5.3

step 1 :
Download the latest firmware for 3gs (iPhone2,1_6.1.2_10B146_Restore.ipsw) and load into phone using itunes.

step 2 :
After loaded phone with 6.1.2. ios, do the following:

Right click the latest redsnOw .exe file and choose properties.
Then choose the "compatibility" tab and check the "run this file in compatibility mode".
Right click the exe and "run as administrator".
Once redsn0w is loaded;
You must choose the "Extra" button and find the lower version 6.0 IPSW file (iPhone2,1_6.0_10A403_Restore.ipsw)
Then Press Back Button and Press Jailbreak, and wait, once menu appears
Click Install Cydia
Click ipad Baseband

step 3:
once phone powers back up, activate the iphone by going through the menus

step 4:
Open the latest redsnOw (redsn0w_win_0.9.15b3) once again and choose the "Just Boot" button
IMPORTANT:
When you do the DFU, keep the home button on the iphone pressed until redsnOw reaches the "reboot" action
If you don't do this you might get the “Exploit Failed” Error.

step 5:
Run the evasi0n 1.5.3 software and follow its instructions

step 6:
Once that is complete, boot the phone and click on Cydia, users, manage.
Then choose "edit" then "add" and type http://repo.iparelhos.com
Then click "search" and type ultrasn0w, chose ONLY to install the ultrasn0w utility (not the fixers)

Once both utilities are installed, reboot and enjoy,