Summary: The popper will mark all messages in the spool 'Status: O'
when the pop connection is closed regardless of what messages were
actually popped.  When the POP connection is lost while popping, all
messages are marked 'O', including ones not fetched.  This causes all
unfetched messages from a broken connection to be silently dropped on
the floor upon next successful pop connection because the pop client is
informed those messages were already seen.

Monty