While running two e-log books that were mirrored, I ended up with the situation of two entries with the same number/id.  The mirroring did what it said it would, increment the local logbook entry and grab the entry from the remote logbook. However, when it did, it did not preserve the fields in the log book that are specified in the config file such as "Author", "Priority", "Subject" ect.  I ended up with a very minimal log: