How to switch a sprint iphone 5s to virgin mobile?

I currently have an iphone 4 with virgin mobile. My friend is getting an iphone 6 so she offered to give me her iphone 5s. The problem is, its from sprint. Being that virgin mobile uses sprints towers i figured that it may be possible to do this. Please help me.

btw her phone is already jailbroken.

You can just flash the Sprint iPhone 5S to Virgin, it will work fine. If you need help with getting the phone flashed to Virgin, mail me.