Sprint/nextel doesn't have sim cards.. even if they did, you would have to unlock the iphone, and never be able to update it. So no it will not work properly with sprint or nextel.
I recently "Bought" Adobe Flash CS3, and i Needed the oval tool for a simple mouth, but surprise, surprise, there is no oval tool, I've seen one on other peoples flash on Youtube in tutorials, but all I have is a square tool.