How to unlock iPhone 4 iOS 4.2.1 baseband 03.10.01?

Hi Guys, I have an iPhone 4 iOS 4.2.1 with baseband 03.10.01. I need to unlock it or the phone is useless for me, I have jailbreaked it with Greenpois0n RC5. I’ve been waiting 2 months for the new Ultrasn0w, but it never comes.
So is there any way I can unlock it?

Thanks In Advance,

I’m not sure but did you do it this way!5754463/how-to-jailbreak-your-ios-421-device ?

That tells how to jailbreak. I Need to unlock it.

But thanks for your help :slight_smile: