Xinetd: unrecognized service

Hello,

I installed NRPE on my Redhat ES5 server using this guide:
nagios.sourceforge.net/docs/nrpe/NRPE.pdf

Everything works perfect.

When i install NRPE on a Redhat ES4 server i get the following error:
xinetd: unrecognized service

Can somebody help me out?

hope to hear from you.

Kind Regards