#15 notification_interval 0

[Luis M]

according to Nagios man pages, when a service
notification_interval is 0, Nagios will send one alert
when needed.
in Export.pm if notification_interval is set to 0, this
option won't be printed to the $CFG, which breaks
Nagios 2.x.

The solution is to simply change this to say:

Line: 1013
print $CFG
" notification_interval
$hash_ref->{notification_interval}\n"
if (defined $hash_ref->{notification_interval}
and $hash_ref->{notification_interval} >= 0);