This will help with the unlocked v400 string........All Cingular devices are subsidy locked as of 11/01/04. Prior to 11/01/04, GSM and GPRS tri and quad devices that contain at least one International Frequency (900 MHz or 1800 MHz) are not locked. This means a customer can insert another SIM into these devices, for example a pre-paid SIM from a foreign carrier. If a customer does this, they will no longer be reachable at their Cingular number and charges will not appear on the customer's Cingular bill.