[CentOS] Perl-related problem on rrdtool?

On CentOS 4.5, I have Cacti and Nagios installed.  I'm trying to
"glue" them together with a program called n2rdd but am having a
problem that I wondering is Perl-related.

When I run "tail /var/log/nagios/rra/n2rrd.log", I see lots of this
sort of thing:

server01: Missing template for "server01" service "check_ping"
"/etc/n2rrd/templates/rra/ping.t"

I have a ping.t template in that file path, but it's still not
working. In fact, I did one exactly like the example in the
instructions (step 7, example 1:
http://n2rrd.diglinks.com/cgi-bin/trac.cgi/wiki/InstallationGuide) and
then I copied that icmp.t template to ping.t

While I don't expect a CentOS list to help me with a non-CentOS,
perhaps someone can tell me if this is a "Perl on CentOS" issue.  I'm
relatively new to installs requiring Perl and assumed I was ready to
go Perl-wise on this version of CentOS

Thanks.