Unable to Verify Apple ID - Email account is not accessible

I have 2 Apple IDs.

I've updated my iPad and iPhone to IOS5, and now I am unable to verify my Apple ID that I use for purchases.

For this Apple ID, I used an email address that is no longer accessible to verify the ID.

I have a money in this account from iTune gift cards, and I would like to use it for purchases.

How can I verify an Apple ID without access to the email account?