If the Nokia 5730 is unlocked it will definitely work with any other GSM network. But make sure that the mobile phone was unlocked safe using an unlock code. Certain unsafe unlocking methods would give problems in accessing other network SIM cards. The safest way to unlock a mobile phone is to unlock using unlock code. You can get the unlock code for a Nokia 5730 from [B]M[/B]obile-[B]U[/B]nlocker.[B]C[/B]om at affordable cost. Once you have received the unlock code, You can visit [B]M[/B]obile[B]U[/B]nlock[B]G[/B]uide.[B]C[/B]om to get the free unlocking instructions for a Nokia 5730. Good luck.