I never changed my student email account to which all app purchases have been made. I just upgraded to iOS 5, and it requires to authenticate the iCloud, by verifying an email sent to the now defunct email address. The problem is that I can't even change my email adress, because the system wants to verify my iCloud account first. It's a circular problem!
Can't change email because I haven't verified iCloud, and I can't verify iCloud because my old email is now defunct.
What can I do??