Here you go mate, heres a Mac version jailbreak green poison, heres a guide on how to do it with this - will work on Iphone4 4.1, 3g/s 4.1, ipod touch 4.1 and ipad 3.2.2
1. Download GreenPoison to your desktop from
http://www.greenpois0n.com/ (Windows, Mac or Linux).
2. Unzip the downloades file.
3. Turn ON your iDevice and connect it to your Computer (Only works for iDevices mentioned above).
4. If iTunes pops up, close it.
5. Turn OFF your iDevice.
6. Execute GreenPoison in Administrator mode (right click to the file, and choose: Run as Administrator). If you dont find the option, just Execute GreenPoison with double click.
7. Click in Prepare to Jailbreak (DFU).
8. Follow the instructions to put your iDevice in DFU Mode.
9. Wait until your iDevice reboot and you see “Jailbreak complete” on GreenPoison.
10. Click on Quit button, and Voilá, you have just jailbreaked your iDevice.