OS X V10.7 Lion :: Cannot Access ICloud Email After Update To 10.7.4

After updating to System 10.7.4, I can't access my iCloud email account on any of my devices (computer and iPhone 4S). The servers are not recognizing my email password, which is the same as my Apple ID password. I can log in to iCloud using Safari and access all of my other information (contacts, etc.), but not email. I tried going to Keychain Access and found that my old MobileMe password was correct (now my iCloud and Apple ID password), but the "application password" associated with my email account (which is now my iCloud email account) had been switched to a long string of nonsense. I tried changing that string to my actual apple ID password, but the system changed it back to the nonsense string.