Got iMessages and FaceTime working using my number on red pocket! :D
after so many weeks googling how to fix this issue, I've finnaly fixed it using a YouTube guide I found on this.
When editting carrier.plist instead of using the +01144 number use +28818773
Contact me if you need any info, keep in mind that I'm just a noob :P
I have a sprint iPhone 4s 5.1.1 unlocked using Gevey sim on Red Pocket, and now I got iMessages and FaceTime working using my number yay! sorry, I'm so excited lol