1.) Ur phone must be ROOT..
2.) U need RoootEx (root Explorer). go to work...
3.) open ur Rootex
4.) Go to system mount as RW
5.) klick and hold build.prop open in text editor
6.) find ro.biild.display.id= (change with every name u want)
7.) restart.
DONE...
Now u use a build number with ur name...