Iphone carrier unlock, jailbreak?

I wanted to ask, can my carrier, Orange UK for example, can unlock my iPhone 4, after i have jailbroken it?
Thank you!

Added (1). I think you did not undersand me, i wanted to ask, if i can jailbreak iphone, and still ask carrier for unlock when contract time is finished?

Call tech support

Call the carrier.

You must have completed your contract before getting unlocked. Even after completing you contract you may need some days to get it unlocked As the process is slow.
If you need to unlock your iPhone 4 immediately, you need to get it unlocked from any trusted third party service. For example, You can get your iPhone unlocked from http://www.superunlockcodes.com/apple-iphone-4/rs16wp9/ using remote unlocking service. This method of unlocking is safe, simple, affordable and quick. All the best mate.