Comex has finally freed JailbreakMe 2.0 Star jailbreak for iOS 4.0.1 (all devices). It’s the first web based jailbreak that lets you jailbreak iPhone 4, iPhone 3GS & iPhone 3G by simply browsing on to jailbreakme.com. Here is step by step guide to jailbreak iOS 4.0.1 with JailbreakMe:
Before you Begin:
- Make sure you’re running iOS4 or iOS 4.0.1 stock firmware.
- Make sure you’re connected to internet via WiFi or Cellular Data Network (3G / EDGE / GPRS).
How to Jailbreak iOS 4.0.1 / iOS4
Step 1: Connect iPhone with iTunes and backup your contacts and data.
Step 2: Browse to http://jailbreakme.com from Safari for iPhone.

Step 3: “Slide to Jailbreak”, once you slide jailbreak process will begin.
Step 4: JailbreakMe will download on your device.

Step 5: Once downloading is complete, jailbreak will progress automatically.
Step 6: Once the process completes, following dialog box will appear.

After that, just exit Safari, you will find Cydia on HomeScreen, enjoy!
Once jailbroken, you can unlock iPhone 4 with ultrasn0w 1.0, Earlier unlock for iPhone 3GS and 3G was possible with ultrasn0w 0.93 and now the latest version of ultrasn0w supports iPhone 4 as well.
How to Unlock iPhone 4
Step 1: Jailbreak iPhone 4 with JailbreakMe. Once Jailbroken, you will find Cydia on HomeScreen.
Step 2: Open Cydia, go to “Manage” tab and tap on “Sources”.
Step 3: Once in “Sources” tap on “Edit” on top-right side, then hit on “Add”. A window will pop up.
Step 4: Enter http://repo666.ultrasn0w.com and hit “Add”.
Step 5: Tap on “Done” on top right corner.
Step 6: Go to “Search” tab in Cydia and search “ultrasn0w”. You should find ultrasn0w in there.
Step 7: Install ultrasn0w (Tap on “Install” on top right corner).
A guide with screenshots is posted here.