BaseBand Upgarde Firmware Downgrade...

[PatHastings]

I have an IPhone 3g Firm - 4.0 Base - 05.15.04
Cant unlock it with the baseband being what it is. I've been looking at 06.15.00, but it says you cannot use "Stock IPWS". If i upgrade to 06.15 can I then restore the firmware back to 4.0?

If not can someone help me out with what i can use?

[i.Annie]

You'd have to take it up to 4.2.1 and do the bb upgrade. If you have SHSHs saved then you can take it back down to 4.0.1, though it might just be beneficial to just stay on 4.2.1 bc it is better than 4.0.1.

Just be aware your GPS breaks if you upgrade the baseband to 6.15.00