If notes are quickly added to an issue within the same second, the notes
share the same date/time stamp. As a result, on occasion, the notes may
appear out of order when viewing the bug. (This situation is more likely to
arise as a result of importing bugs.)

In bugnote_view.inc.php, I would suggest changing the SQL SELECT as follows:

< # get the bugnote data
< $query = "SELECT *
< FROM $t_bugnote_table
< WHERE bug_id='$f_bug_id' $t_restriction
< ORDER BY date_submitted $t_bugnote_order";

to:

   # get the bugnote data
   $query = "SELECT *
                   FROM $t_bugnote_table
                   WHERE bug_id='$f_bug_id' $t_restriction
                   ORDER BY date_submitted,id $t_bugnote_order";