How to port Siri to iPhone 4 if I have a 4S?

Hi, does anyone here knows how to or have a link that tells me how to port a fully working Siri over to my iPhone 4 if I have an iPhone 4S in my possession?

 

A lot of tutorials online teaching how to port the Siri GUI over with no functionality. I do have access to an iPhone 4S, so I am wondering if i can follow those tutorials but modify some system files on my iPhone 4 to bluff Apple's server with the UDID of the 4S that I have access to?

The 4S in question actually belongs to my girlfriend, so I believe the combined usage from the both of us shouldn't be so high as to alert Apple of unusual traffic I assume? She rarely uses her Siri anyways.