I am a Malaysian working in the United States and need to
travel between the United States and Malaysia frequently. I am using the Samsung SGH-c207 (Cingular as the provider). I like my phone and wish to use it while I am in Malaysia. When I put in the SIM card I bought from a local service provider in Malaysia, the phone displayed "WRONG CARD".

Could you please tell me how can I unlock this phone so that I can use it both in Malaysia as well as the United States (just swapping the sim cards). Your help is greatly appreciated and thank you.