[clug] Nagios show status information as (null)

[Jeffm]

Have this annoying problem with nagios I'm hoping the local nagios 
experts can help me solve. Search the web hasn't turned up anything 
useful (eye strain doesn't count as useful).

I'm using nrpe to run remote checks on a machine. I have two dummy tests 
and a real one which I'm developing.

The first dummy one, as written in the nrpe cfg file, is,

   command[check_ok]=/bin/bash -c 'echo "Hello"; exit 0'

this works fine.

The second dummy test was added to check that it wasn't a python 
specific problem I was having,

   command[test_py]=<path-to-script>/test_py.py

where <path-to-script> is the location of the script. The script in turn 
says,

   #!/usr/bin/python
   # Minimal python test

   import sys

   print "OK w/ exit"
   sys.exit(0)

The real script ends in the same two lines and has all three tests have 
very similar setups in the nagios config. All three scripts return 
correctly when called via check_nrpe on the command line from the 
machine nagios is running on, eg,

$ ../libexec/check_nrpe -n -t 20 -H <hostaddress> -c test_py
OK w/ exit

and return an exit code of,
$ echo $?
0

However, the real script under development fails within nagios with the 
web interface displaying the Status as WARNING and the Status 
Information as (null).

Is there anything I should be looking for? The only thing I can think of 
at the moment is timeouts, but the script real script runs in under 
0.050 seconds wall time so that's not it.

Jeff.