Unlock iPhone 2G, 3G and 3Gs firmware 3.1.2 with Blacksn0w

Did you upgrade your iPhone recently to firmware 3.1.2 ? And losing signal since then?
Now is the lucky day...
You can unlock 2G, 3G and 3Gs iPhone firmware 3.1.2 now with Blacksn0w..
How? :
1. Jailbreak your iPhone with Blackra1n ( see tutorial in other part of this blog)
2. Turn on cydia
3. Press manage
4. Sources
5.edit
6. Add
7. Type http://blackra1n.com
8. Add source
Back to cydia
Then you will see a new Repo written Blackra1n. Press it-install-confirm

REBOOT and insert SiM card..
that is it...done