[Nagiosplug-help] Return code of 127 (Plugin not found?)

[Edward Ocampo-gooding]

I have a plugin that I wrote in Ruby for checking an Oracle db that
works fine on one server (Gentoo), but doesn't on another (Red Hat
Enterprise Ed.).

The error I get from the Red Hat Nagios setup is:
Return code of 127 is out of bounds - plugin may be missing

I ran /usr/bin/nagios -v /etc/nagios/nagios.cfg on the Red Hat machine
and the pre-flight check came out clean.

I ran the plugin manually as user "nagios" and confirmed that it works
(on both servers).

I've checked permissions and the existence of the plugin, but can't
seem to find any clues as to why this isn't working.

Any ideas?

Thanks,
Edward