This happened during a sync of my iPhone while installing some apps. This usually happens to non-jailbroken iPhones who are trying to install non-Apple approved software OR jailbroken phones who haven't done the "Sync update".
How to fix this error and get the Sync Update
Open Cydia - Manage - Sources - Edit
Add this source: http://cydia.hackulo.us
Then under the section "Hackulo.us" install "Ap........