GPP/r-sim 3 does work and it will unlok ALL ATT version 5.0/5.0.1/ 5.1 and firmware 1.0.11/1.0.13/1.0.14/ 2.0.10 and for SPRINT and VERIZON will unlock 5.0/5.0.1 only.
here is the prove i did it and it work.
i guess...we are back to step one using sim unlock. Well, with sim unlock like GPP/gevey/ r-sim3 its easier to use most of the 4s dont have to be jailbreak unless you are on sprint and verizon.