I am trying to migrate account from a server running Zimbra 7.2 to a server running Zimbra 8.0, both OSE. I tried a few accounts, some working flawlessly, other failing with this message:

Response Message: Could not initialize class com.zimbra.cs.service.formatter.FormatterFactory

(some other failed due to an upload size too large, which I modified already).

What does this error mean?