Hi Jack,
Thank you, exactly what I was looking for.
I lost some hair over figuring out how to activate iMessages and FaceTime.
I even followed advise that helped others, mentioned here. Although I followed the advise mentioned in the link, I was unable to activate, I then reset and restored from a iCloud backup. Unfortunately I could not access an iCloud backup from more than a month ago, before I left for Thailand, where I got a prepaid sim that latched on to my iMessages and FaceTime account with the Thai prepaid number.
Now I'm back home in Japan and cannot seem to shake off the prepaid number from Thai.
Anyway, after the hard reset and restoration from iCloud, following many ideas online of setting date and time to automatic, I managed to get iMessages to register my Japan number, YaY!, however FaceTime was still not getting activated. I came across your solution and called immediately. The iMessage number worked I heard some automated message spoken in an British accent. My iMessages was already activated anyway...
My problem is when I dial the number to activate FaceTime I get a voice message from my Service provider saying "please check the number you have dialed" I tried all variations of adding "+" and "00" before the number. Nothing worked, even sending a message to the FaceTime number you mentioned, didn't work.
I figured if I could send a message and call the iMessages number you shared, I should be able to do the same for the FaceTime number.
I am lost and I need to fix the problem for peace of mind!
Request you to pleas share how I can get a hold of the latest numbers, if the numbers you provided are fixed for all iOS versions (I am on iOS 6.3.1), what else I can do to fix the problem.
Thank you so much though, I felt like I was loosing my mind till I understood how the activation system works!