The Redsn0w 0.9.5 beta 5 is compatible to jailbreak iOS 4.0.2 on iPod Touch 2G (Non MC model) and the iPhone 3G. So if you are planning to jailbreak your iPod Touch 2G (Non MC model) running iOS 4.0.2, then here is a guide to do that. Just do the below steps correctly.
NOTE : You should have the iOS 4 .ipsw file for iPod Touch 2G for this to work.
1. Download Redsn0w 0.9.5 beta 5 for Mac OS X or Windows.
2. Download the iOS 4.0.2 firmware for iPod Touch 2G from here.
3. Update your iPod Touch 2G to iOS 4.0.2 using iTunes.
4. Launch Redsn0w and browse to the iOS 4 firmware file (Not the iOS 4.0.2 firmware).
5. Check the â€ Install Cydia â€ box and click â€ Next â€œ.
6. Now switch off your device but keep it plugged to the computer.
7. Now go into recovery mode by pressing the power and buttons for 10 seconds and then release the power button, but keep holding the home button until the iPod Touch 2G iOS 4.0.2 jailbreak process begins.
8. Now wait till Redsn0w jailbreak your iPod Touch 2G running iOS 4.0.2 firmware.
9. Reboot your iPod Touch and it will be jailbroken on iOS 4.0.2.