As we know, iPhone Dev team has released a beta version of redsn0w tool to jailbreak iPhone OS beta 4 on iPhone 3G devices. This redsn0w 0.9.5 beta is developed for developers so that they can upgrade apps for final iPhone OS 4.
Before jailbreaking iPhone OS 4 beta, you must read the guidelines and important notes given by Dev team. If you are ready to jailbreak iPhone OS 4 beta with redsn0w 0.9.5, follow the steps mentioned below.
Guide to Jailbreak iPhone OS 4 Beta with Redsn0w 0.9.5
Requirements:
- iPhone 3G
- Mac OS X
- iPhone OS 4 Beta
- iTunes 9.1
- Redsn0w 0.9.5 – Download Link
Steps to follow:
1. Install iPhone OS 4 Beta (iPhone1,2_4.0_8A230m_Restore.ipsw) on your iPhone 3G.
2. Download Redns0w 0.9.5 tool to your desktop and run it.
3. Browse the iPhone OS 4 file and select it.
4. Now, install the ‘Cydia’ tool.
5. Put your iPhone 3G in DFU mode with instructions displayed on the screen.
6. Wait for few minutes to complete the jailbreak process.
7. When the process gets completed, iPhone will restart automatically.
8. Since Cydia is not properly updated for iPhone OS 4, you will have to add following repo in blank sources.
REPO: http://apt.saurik.com/cydia-3.7
9. Restart the iPhone to get regular Cydia app.
Well, that’s it! You can now play with your jailbroken iPhone 3G.
Disclaimer: The guide is only for information purpose. Follow above steps at your own risk.
Update 1: Unlock iPhone 3G OS 4 Beta with Ultrasn0w 0.92
Update 2: Download Redsn0w 0.9.5 Beta 2 to fix SMS & 3G Data Failure Issues
Also see:
- Guide to jailbreak iPhone 3.1.3 with Redsn0w 0.9.4
- Guide to jailbreak iPhone 3.1.3 with PwnageTool 3.1.5
- Blackra1n for iPhone 3.1.3 Firmware


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