how to unlock my sprint iphone 4
I am traveling to another country for 2-weeks.
How do I unlock my sprint iphone4 to accept a sims card?
You don't. The Sprint iPhone 4 doesn't even have a SIM slot. There is no GSM radio in it. It is a pure CDMA phone. It will never work with any carrier other than Sprint.
Buy a cheap disposable phone when you get to the country you will be visiting.