from src/etc/rc.d/ntpd: required_files="/etc/ntp.conf"

I'm wondering having in my rc.conf legal assignment:

ntpd_flags="-A -c /etc/ntpd.conf -f /var/db/ntpd.drift \
-l /var/log/ntpd.log -p /var/run/ntpd.pid"

Why /etc/rc.d/ntpd script requires /etc/ntp.conf file as a config file
for NTP daemon? This file even isn't exist by default (cause ntpd is
contributed software, right?), so system administrator should create new
file, named by his own rules. Often it'll be ${name}.conf -> ntpd.conf.
So i see there 3 different ways to fix this (wrong?) behavior:

1) Simply fix src/rc.d/ntpd (here's THE PATCH =))
"--- /etc/rc.d/ntpd      Tue Aug 24 03:12:38 2004
+++ /usr/src/etc/rc.d/ntpd      Sat Jul  3 01:38:57 2004
_at__at_ -15,7 +15,7 _at__at_
 rcvar=`set_rcvar`
 command="/usr/sbin/${name}"
 pidfile="/var/run/${name}.pid"
-required_files="/etc/${name}.conf"
+required_files="/etc/ntp.conf"
 
 ntpd_precmd()
 {"

2) Add new variable "ntpd_conf" to rc.conf (and use it in etc/rc.d/ntpd
rc.ng) which will represent path to ntpd config file (default to
etc/ntpd.conf in etc/defaults/rc.conf). 

3) Somehow (gtopt(1)?) parse ntpd_flags variable from rc.conf to find
what is after "-c" and use it in etc/rc.d/ntpd.

Thanks, for your attention.