Cannot Process SNMP Traps

[Russ W. <ru...@so...>]

Hi,

I am attempting to receive traps from various devices on my network 
(Copper Mountain DSLAMs, Cisco routers, etc.) so that I can then funnel 
the traps into Nagios for network monitoring.  However, nothing I have 
tried for the last three or more months has allowed me to receive/handle 
any traps sent by any devices.  Below are some relevant files and 
configuration.

10782 ?        S      0:00 /usr/sbin/snmpd -Lsd -Lf /dev/null -p 
/var/run/snmpd.pid
10784 ?        Ss     0:00 /usr/sbin/snmptrapd -Lsd -p 
/var/run/snmptrapd.pid

snmptrapd.conf:
traphandle default /usr/local/bin/traphandle.sh default

traphandle.sh:
#!/bin/bash

LOGFILE="/tmp/snmptrapd.log"

case ${1} in
   default)
     echo -e "Found default trap:" >> ${LOGFILE}
     echo -e "${*}\n" >> ${LOGFILE}
     ;;
   *)
     echo -e "Found unhandled trap:" >> ${LOGFILE}
     echo -e "${*}\n" >> ${LOGFILE}
     ;;
esac

exit 0

snmp.conf
mibs ALL

I have the Copper Mountain MIB located in /usr/share/snmp/mibs, where 
all of the other default MIBs are located.  When run in debug mode, the 
snmptrapd output shows the Copper Mountain MIB is processed.  When I 
bring up and drop an interfaces on a Copper Mountain DSLAM, tcpdump on 
the receiving host running snmptrapd shows:

09:36:35.926828 IP 172.20.7.2.1966 > 
ldhl-sentry.natcotech.com.snmp-trap:  C=Natco Trap(36)  E:1996 
172.20.7.2 enterpriseSpecific s=12 132246500 .iso.org=[|snmp]
09:37:14.772609 IP 172.20.7.2.1967 > 
ldhl-sentry.natcotech.com.snmp-trap:  C=Natco Trap(36)  E:1996 
172.20.7.2 enterpriseSpecific s=12 132246890 .iso.org=[|snmp]

So I know the trap packet is being received.  But the file 
/tmp/snmptrapd.log referenced in the traphandle.sh script never has 
anything in it.

Can someone please help me figure out why I have never been able to 
receive or process SNMP traps using net-snmp--before I go stark raving 
mad?  If someone is able to work with me via phone or IM in an 
interactive way, that would be greatly appreciated.

Regards,
Russ