Unlocking my jailbroken iPhone 4?

I'm connecting my sprint iphone very soon, but my phone is jailbroken. I soon have to unlock my phone to T mobile. I really want to because I will finally have a data plan and actually get to use my iphone as a iphone. But i have some questions, please answer them?

1.) will unlocking my phone take away my jailbrake? ( if so i'm seriously not unlocking it)
2.) will they unlock my phone even if it is jailbroken

Unlocking your phone will NOT remove your jailbreak. And if your baseband is low enough you can unlock it for free (but that is very rare). If you want your iphone unlocked i can do it for you.

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