Lets stay someone has an old Cingular Sim. would it be theoretically that person clone a tmobile sim onto that cingular sim and use that since the Ki number is still present on the cloned cingular sim?

Originally Posted by iboner

Lets stay someone has an old Cingular Sim. would it be theoretically that person clone a tmobile sim onto that cingular sim and use that since the Ki number is still present on the cloned cingular sim?

You can not, as far as i know write to sim cards. Data is protected.
If possible, this would not work. Use silvercard.