Very recently, we informed you about the arrival of redsn0w 0.9.5, the first iPhone 4.0 jailbreak tool. This tool as you will remember has few limitations since it is available for Mac platform only and supports iPhone 3G devices only (for the moment). The next requirement would be the steps to perform to jailbreak your iPhone 4.0 Beta firmware which are listed after the jump.

Pre-requisites

  1. Upgrade the firmware on your iPhone 3G to iPhone 4.0 Beta.
  2. Make sure you’ve already activated your iPhone 3G with iTunes and your developer UDID
  3. Launch the beta redsn0w 0.9.5
  4. Select your stock iPhone1,2_4.0_8A230m_Restore.ipsw file (you’ve already used this to update your iPhone3G to 4.0beta1)
  5. Select Install Cydia and click Next. Use DFU mode (See how to guide here) to install the jailbreak.
  6. When your iPhone3G comes back up, you’ll notice Cydia has a blank white icon (we told you many things were broken right now!) You’ll also notice Cydia has no sources. Go to the Sources panel and add this repo: http://apt.saurik.com/cydia-3.7 (be sure you have a carrier or wifi signal first!). When Cydia restarts, you should see its real logo now, and the standard sources should be ready to use.

Once you are done with the jailbreak part, your next step is to downgrade the baseband from 05.13.03 to 04.26.08. You can use the updated Fuzzyband to do that, the guide to which can be found here.