Help me unlock my iPhone please

[MilanoChris]

I bought a 3G from my brother. It is an ex O2 contract phone and I am waiting (impatiently) for O2 and get it unlocked. He told me the phone is on 3.1.3 which I have confirmed.

I have managed to Jailbreak the phone using a combination of Sn0wbreeze and redsn0w. Once I got this done and after waiting for Cydia to download all its bits I am looking at unlocking the phone to use my Vodafone SIM with it. I am also slightly confused as to how I did this (more than once, I might add) when there is a sticky in here saying it's not possible to do this?

It is suggested on the internets that the only way unlock the phone for my baseband is by using blacksn0w, however this just crashes the phone once it is installed and the only way that I have so far found to get the phone back to working order is to do a full restore via the OEM 3.1.3

Any pointers please? Yes, I know I should wait till O2 unlock the phone and do it that way but I am very impatient and I am selling the phone that the iPhone replaced so the sooner the better.

 

[LVCIFER]

If your baseband is 5.12.07, it flat out cannot be unlocked. Not yet.

 

[MilanoChris]

Yes that is the baseband. Looks like I'll sell it on then, especially as I broke today and got a 32GB 3GS. Thanks for your reply.

 

[LVCIFER]

You won't get too much for it on stock 3.1.3 though.

 

[Crunch]

If you need the money, by all means, sell it. If you can wait, there should be a way sooner or later.

 

[MilanoChris]

I paid ?100 for it, so I figure I can make that back easy and some more. I think I'd be able to get at least ?150 for it which will go toward the ?180 I paid for the 3GS today.