Error 1015 while downgrading and jailbreaking

[Jυsтιи]

I want to downgrade my 3g to 3.0 and jailbreak it. I downloaded pwnage and 3.0 3G firmware, created the custom firmware, and put my phone in DFU mode. When I try to restore my phone, I get error 1015 on both the custom and normal 3.0 firmware. I searched the forums but all the solutions involve using windows. So, um, help?

Phone: 3G
OS: OS X 10.5.8
Itunes: 9.0

Edit: Just downloaded the new pwnage and 3.1 firmware and jailbroke the phone that way. Maybe that will fix the silly issues that 3.1 has. Should work now, but I'll post if it doesn't.