I have installed the check_snmp_cisco_memfree plugin and it works great from the command line when i type:

./check_snmp_cisco_memfree -w 70 -c 60 -h -s xxxxx
that will return:

MEM OK [74% free (45503k of 181338k in use)]

However when I try to integrate it into nagios I get SNMP error under the status information. Can anyone tell me what may cause that. Or please provide how I would set up the command and service for that plugin to make sure I am doing it right.