in my project i have a Third Library that don't have the armv7s slice for the new iPhone, so i want to know how i can set the Project Target Architecture, and the Third Library Architecture to work with iPhone 5...
You can simply remove armv7s from Valid Architectures in your build settings.
See File is universal (three slices), but it does not contain a(n) ARMv7-s slice error for static libraries on iOS, anyway to bypass? and Facebook SDK for iOS6/Xcode 4.5 not working.