On Red Hat based distros you'll usually find daemon parameters under /etc/sysconfig/<daemon>, on Fedora mine contains:
Code:
]# cat /etc/sysconfig/ntpd
# Drop root to id 'ntp:ntp' by default.
OPTIONS="-u ntp:ntp -p /var/run/ntpd.pid -g"
Just add the '-x' to the end of the OPTIONS but inside the double quotes.