D3 SIM unlock

[macten52]

I am sure this has been asked and I have attempted to search but haven't really found the answers I am looking for....

Is it possible to unlock a D3 so it can be used on a US GSM network ie ATT etc. ????

Several US prepaid vendors are now offering SIM only prepaid services. this would be great and a lot cheaper for a teenager.

Thanks in advance.