If you enter the value below without $g_ and replacing ON with 1 and NOBODY with 55 and 100. You will notice that the array will show up in the configuration with quotes around the numbers like '1', '55', and '100' where it should be numbers.

$g_default_notify_flags = array('reporter'  => ON,
                                'handler'   => ON,
                                'monitor'   => ON,
                                'bugnotes'  => ON,
                                'explicit'  => ON,
                                'threshold_min' => NOBODY,
                                'threshold_max' => NOBODY);