Install NTP from source code

Install NTP from source code

I am trying to install NTP 4.2.2 using the source code on Oracle
Enterprise Linux oel6 (distribution based on Redhat 6) so that it's
execution can be instrumented for study purpose. After the following
simple steps, the installed NTP seems to be not recognized by the OS.
./configure
make
make install
The compile and install seemed to complete successfully, but it was not
recognized by the system. The following start up command failed because
the script cannot be found.
/etc/init.d/ntpd start
Another script /usr/local/bin/ntpd was found, but it was not the startup
script.
When using the normal yum command to install NTP (i.e. yum install ntp),
the /usr/local/bin/ntpd script was not overwritten. It was not removed
(after yum remove ntp).
Question: What could be wrong with the installation procedure ?