Does an orange sim work in a locked t-mobile iPhone 4s?

Does an orange sim work in a locked t-mobile iPhone 4s?

No… When its LOCKED, that means it will only work for 1 carrier---tmobile in your case

you have to jailbreak it, unlock it via cydia app, and THEN pop in your orange sim card…

No; you'll need to unlock the iPhone.

No it's locked: p you'll need to go to a phone unlocking store. You'll hand it in to them for several days and they'll unlock it for you. It's quite expensive though for what they are doing