Problems running multiple nagios instances on one server

I searched for similar threads, but came up empty, sorry if this is a repeat question,

I want to run multiple nagios instances on a single server. I’m running nagios 3.0rc3 and nagios-plugins 1.4.11 on Solaris 9.

The nagios software is installed in /usr/local/nagios, and is available from there to the nagios server and all monitored clients.

I have a separate local directory for each nagios instance (e.g, /local/nagios1, /local/nagios2, etc) that contains the config files, logs and log archives, external command file, etc. (everyhhing in nagios/var, nagios/etc and nagios/share)

Testing each config file, nagios recognizes the correct number of hosts and servers, and returns no errors. Each nagios instance starts up without errors. However, the log file indicates thet each instance is receiving check results from hosts/services on the other instance… I see messages like this in /local/nagios2/var/nagios.log, when the host “hadar” is configured in the /local/nagios1/etc/hosts.cfg config file:

[1204870487] Warning: Check result queue contained results for host ‘hadar’, but the host could not be found! Perhaps
you forgot to define the host in your config files?

I’ve checked the nagios.cfg files for both instances, and each refers properly to files in it’s own path. What am I missing here?