iOS 7 defaulting to old iCloud email address and I can not remove it or reset

Hi, since up-dating my iPhone 5 to iOS 7, iCloud shows (greyed out) my old email address used for my Apple ID.

Becuase of the new 'Find My iPhone' feature I can not remove it or reset it. I'm asked for a password but of course that old password is not assocaited to an active account anymore.

I backed up to latest iTunes but again becuase of the new feature I am unable to reset and restore from back up my iPhone without that old inactive password. My old password will not work becuase I have a new iCloud / Apple ID email address.

I am also unable to sign in to iMessage using my Apple ID, keeps telling me to check my network connection, which is fine. I assume Apple servers just in major overdrive with downloads, or is the problem connected to my main issue above?

Anyone else getting the same problem? Anyone got a fix?

Thanks

Chris