I got the same problem,waiting for and looking for the solution now.
I did everything like:
1.change the wifi DNS to 188.8.131.52.,184.108.40.206
2.restore the phone setting and the net setting.
3.reboot the phone(press the HB button and power button at the same time).
4.reset the network.
5.take out the sim card,only use wifi to activate the FT and iMessage
and all those make no difference to me phone and iPad.
anyone got a solution? I am really greatful...