PwnageTool 3.0 to Jailbreak iPhone 3G 3.0 On Mac OS X RELEASED BY DEVTEAM
Quickpwn has not been released but the PwnageTool 3.0 has, unfortunately this version is only for the macs. It will allow you to create a custom .ipsw file that you can then use to restore the iphone. Once it is restored it will be jailbroken and the baseband will be unlocked.
The Pwnage tool will work on the following devices (Ipod Touch 2G, Ipod Touch 1st Generation, Iphone 1st Generation, and finally the Iphone 3G) This will not work on the iphone 3GS. Below is the download links to the PwnageTool 3.0 for mac. This tool allows you to create custom firmwares that you can use to restore your iphone. Follow the tutorial in the link and you will be able to jailbreak your iphone quickly and easily.
Pwnage 3.0 Download for mac:
Here is a Step by Step tutorial I found on www.ismashphone.com