Just did the upgrade and restore from my 3gs -> 4s. Went pretty smoothly, except when I go to the voicemail, it says "Cannot Connect to Voicemail". Anyone else have this issue? Is it just a problem with busy AT&T servers, or what? I noticed I had to re-enter my password for all my email accounts after the restore. I thought this could be the problem, but in the phone settings, there is no password reset option.