Requirements:
-iPhone 4.
-Orginial iPhone 4 SIM -no service- is worked --- we'll name it x
or gevey sim you can select carrier
-SIM card with constant data availablity. check it with unlocked mobiles if it has constant data, because if not ..it won't work for you! --- we'll name it 'o'
-Time.
-Luck .

Pre installed apps needed.
install in cydia SAM.
Go to cydia >> manage > edit > add > add this source
http://repo.bingner.com
then install SAM.
and restart springboard.


Presettings.
wifi = on. Just for the moemnet
Go to Settings>>General>>Network
MAKE SURE THAT YOU TURNED "ON" THE DATA ROAMING AND CELLULAR DATA.
Service Location Must be OFF completely off.




keys.
carrier x . offical iPhone Carrier
carrier o . the carrier which we'll use to unlock the iPhone.


Steps

STEP 0-open SAM then go out the app using home botton "LET IT OPEN"


STEP 1-First of all you need to go to Unlockit - APN Changer for your iPhone (in your iPhone) and download your unofficial carrier profile (carrier o).

STEP 2. Insert your official iPhone SIM CARD "x" and dial any number , if no service dial 112.

STEP 3. Go to settings>Carrier and turn of auto search then select the network which you will use to connect in next steps (i mean carrier o). you will met a message "Restricted network ... bla bla bla..".

STEP 4.hit Dismiss . then go back to main settings menu.

STEP 5.turn on airplane mode.

STEP 6. go fast to SAM>>utilities>> and press to deactivate iPhone , Deactivate push "Clear certs"


, restore lockdown to stock... go back check if SAM is in "Desabled" mode.

STEP 7.after this step you have to forget wireless networks. and turn off auto connection

STEP 8. go to cydia>> manage > sources then "bingner" then uninstall SAM. Donít "restart springboard" now!

STEP 9.after uninstalling sam / press home button >> and go to settings then forget the Wi-Fi network~.

. make sure airplane mode is ON

.Eject the Carrier X sim/ press of the no sim installed.

STEP 10. Go back to cyida and get ready for inserting the next sim (Carrier O).

here is the fast step!

STEP 11. press "Restart Springboard" and insert the (carrier O) Sim card Before apple Logo "i mean normal restart springboard" progress indicator.'

STEP 12. you will met the regular apple activation screen. with (E) just wait 30 seconds.

STEP 13. turn off your iPhone. then turn on. the sam activation screen you'll met "now with one signal bar" and E data connection.

STEP 14.you'll see "use cellular connection" press it and wait 5 to 8 seconds

STEP 15.eject your sim then reinsert it fast. you will redirect to home screen!.... with full signal bar "Carrier O" network

go fast and call service center for 1 minutes "auto reply services center" of carrier O.

now go to settings>General>about and check your carrier: it must be "Carrier 11.0".

... you'll have your iPhone like a factory unlocked. Congrats.

STEP 16. enjoy calling your best friend or Baby as second call.

unlocked it no problems so far.
now your iPhone 4 in baseband 4.11.08 is unlock


Tip: You can reinstall Sam and get push notifications and iMassage also facetime

this steps works MC318LL my friend reported that is worked with MC319LL...


keep trying it won't tire you more than its worth

**** sorry for my english****
NO ORIGINAL SIM CARD
Update 2 : If you don't have your Original SIM, try to get out of "invalid sim"... you to "get searching" while last steps of activation if have gevey SIM maybe help full to select carrier!.

SAM OVERLOAD- NO SERVICE - NO DATA (E).
update 3 : SAM maybe overloaded! keep trying. if you getting no service , USE SIM Card that provide a constant Data ... some cards Data activated as requested by Carrier! and check pre settings. Roaming data must be ON

NO ACTIVATION SCREEN APPEAR ?
Check step 6. and step 8. its Updated

worked in iPhone 4 MC318LL with this networks. UAE : du , etisalat. Jordan: Orange , zain and Umniah