Question about using European Samsung in Thailand (Bangkok)

Hi,

Does anyone have experience in using a Samsung smart phone bought in Europe in Thailand. The phones here say only for European SIM cards. According to Samsung *usually* the phones can be used with non-European SIM cards after a 5 min call has been made using European SIM cards. However, there may be operator specific issues. Any experience of successful / unsuccessful use of Thai SIM cards in phones bought outside of Asia. If possible, please tell from which country the phone is from and which Thai operator you tried to use.