Can you unblock/jailbreak an iPhone 4s that's been on t mobile contract?

And it was blocked b4 the contract was finished

Yeah man, you can jailbreak any iPhone even if it's on a plan/contract, I have mine done I did it myself, but you can only do it on software under IOS6.1.3, you can't jailbreak 6.1.3, and use the jailbreak software called "Evasi0n"