In the older version of CentOS or Fedora, xinetd daemon was usually installed by default. However, it seems ( I may be wrong) that from CentOS 5, this is not the case. So if you noticed your xinetd daemon is NOT present in your /etc/inet.d but the xinetd.d directory are present. Just run the usual
# yum install xinetd
And it is ready for your use.
