how can i unlock and jailbreak iphone 3gs on 4.0.2?

[Brad]

untethered unlock and jailbreak

[vimal09]

Here is the steps to jail break the iphone
Step 1: Download the jailbreak program of your choice to your computer.
Step 2: Connect your phone to your computer and turn it off.
Step 3: Run the jailbreak program, carefully following its instructions.
Step 4: Choose your phone`s IPSW file for its firmware.
Step 5: Select what you want to do with your phone among the firmware`s options such as installing Cydia or installing an iPad baseband for unlocking.
Step 6: Place your phone on DFU mode by pressing and releasing the Home and Power buttons. The program will tell you exactly how to do it. there are many software available to unlock iphone and i unlocked it by remote unlocking..
there are many online providers who provide the service..one of my friend got unlocked his iphone from Theunlockarena.com by remote unlock..and the important thing remote unlocking is available for some country and network providers only so if you are interested you can try from them before that see whether remote unlocking is available for your country and provider.