This guide teaches you how to jailbreak your iPhone 2G/3G (NOT 3GS) on the 3.0 firmware using Pwnage Tool 3.0 by the iPhone Dev Team. ONLY WORKS FOR OS X.
You can unlock your iPhone 3G AFTER following this guide by using UltraSn0w. Directions on that are here. If you want to unlock your iPhone 2G while Jailbreaking follow this guide. Anyways, lets continue.
Before getting started, you'll need to download a few things:
Pwnage Tool 3.0 - MMi Member Download | RapidShare | torrent
3.0 iPhone Firmware iPhone 3G Direct from Apple (iPhone 2G Firmware is here)
Note: Safari does not download the .ipsw files correctly - it decompresses them as soon as they're downloaded. We don't want that. Use Firefox to download the .ipsw, not Safari. Or you can ctrl+click the decompressed folder & click the compress button.
Alright, now that you've downloaded all that, lets continue.
Connect your iPhone to iTunes.
I recommend you sync up first so you get your contacts, photos, mail, etc current.
Note: restoring will remove any and all Jailbreak app settings and WinterBoard themes. bhz has a decent guide on how to back all that up here if you'd like. Otherwise, you can just redownload them.
Once you've downloaded the 3.0 firmware and placed it anywhere (I just put mine on my desktop) (or in your Applications folder) you can open Pwnage Tool by double-clicking the icon.
You may have OS X ask you about opening an app from the internet, don't worry about it - click Open.
Hit OK on the Copyright screen that pops up.
Since we're going to be jailbreaking our 3G iPhone, click that image on the left so the green checkbox comes up, and the hit the blue arrow button in the bottom right to move on.
On the next screen, Pwnage Tool will look for the 3.0 .ipsw file. It should find it automatically (again, mine was on my desktop), and list it there. It will take about a minute to find it. Click it and hit the blue arrow in the bottom right to move on.
Note: If you want a larger main partition (for installing Cydia apps and themes, etc), click the Expert mode and then the General icon, and increase your parition size.
Pwnage Tool will then let you know its going to create an .ipsw file.
Next, you'll be asked if you have a contract that would activate normally through iTunes - this is AT&T only in the US, or any other carrier outside the US that is a legit iPhone carrier who you bought the iPhone through. ''IF'' you have a legit contract with iTunes (e.g, you have AT&T or an approved iPhone carrier in another country) - say yes.
Once you've answered those q's, Pwnage Tool will begin creating your .ipsw. This screen should be up around 5 minutes or so.
Halfway through the creation of the .ipsw, OS X will ask you for your password. This is required for Pwnage Tool to build the custom firmware, go ahead and input your password and hit OK.
Pwnage Tool will ask if your iPhone has been previously pwned (and still is). If you aren't sure, just hit No, that's fine. If you know for sure its been pwned and still is, hit Yes, but make sure it really is.
Once complete, Pwnage Tool will let you know to quit Pwnage Tool, put your iPhone in Recovery mode (OR DFU MODE if you've never pwned), start iTunes, and restore with the custom firmware bundle it just created.
Now, pull up iTunes. You should see the following message:
Hit OK. Now, this is important - where it says Restore in iTunes, hold down the ''option'' key on your keyboard and press ''Restore'' in iTunes while holding it down.
Note: Its very important you hold down the option key while pressing Restore. Don't forget that.
Assuming you did that correctly, a window should pop up asking you which .ipsw file you'd like to restore from. Select the one we just created with Pwnage Tool. If you left it default, it should be sitting on your desktop and be named iPhone1,2_3.0_7A341_Custom_Restore.ipsw or something similar. Hit Open.
iTunes will now run through its typical flurry of windows and notifications while updating the firmware.
During this time, you'll see the nifty new progress bar on your iPhone as it restores.
If everything went correctly, you'll see the window stating your iPhone was restored to factory settings (heh, not quite, iTunes , and you can then hit OK.
Wait for iTunes to see the iPhone before disconnecting.
If you'd like, you can now restore from the backup you made of your iPhone before, to get all your contacts, mail accounts, and photos back. You might wanna clear off some photos/videos/music if you had it near full to make room for AppStore and Cydia apps now.
Congrats! That's it! You're now ready to go on iPhone firmware 3.0.