found this on apples discussion forums, anyone get it to work?
Has anyone tried calling the iMessage and Facetime server's activation number?
The purpose of the SMS is for Apple's server to verify this phone actually owns the phone number. So when iMessage / Facetime is activating, it sends a shortcode text to Apple. But since Wind doesn't support the short code, there has been some users reporting calling the actual number seems to work.
1. Turn on iMessage. When the text says 'Waiting for activation...'
2. Call the activation server number for iMessage: +445773142076
or Facetime: +447786205094
NOTE: This is an international number to UK.
3. Usually after a few minutes it will activate.