Default [Q] Using "Unlocked" SN2 in Germany?

My boss has a GN2 from Sprint and he wants to use it in Germany but he's not unlocked and not rooted. He wants to know what he has to to do use this phone in Germany - last time he went, he used an unlocked Moto Razr and just tossed a sim card in.

I have a T-Mobile Note 2 and I have a sim card, can I unlock mine (rooted, etc) and use a german sim card in there?
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