Dynamic DNS configuration......

I have been trying to setup a small dynamic dns server with dhcp.  I have been 
scouring the net and everything I find seems to suggest that it is possible 
with RH7.3 but I starting to thing they are wrong.  

I found a common suggestion to load the following:
{
ddns-domainname "fortleboeuf.net";
ddns-update-style interim;
ddns-update-style ad-hoc;
ddns-updates on;
}
in the dhcpd.conf


But when I try to restart dhcpd, I get numerous erros like 

{
etc/dhcpd.conf line 2: expecting a parameter or declaration.
ddns-update-style
^
Configuration file errors encountered -- exiting
exiting.

}

I have found web info about this error on older version of rh that say it's 
because ddns was not possible.  

Anyone have experience with this?  

Thank you.

-- 

Michael Cortes
Fort LeBoeuf School District
34 East Ninth Street
PO Box 810
Waterford PA 16441-0810
814.796.4795