SNMP Trouble

I had Sysmon v0.92 working, but wanted SNMP support, so I installed
ucd-snmp 4.2.6, then reinstalled Sysmon (I also tried net-snmp 5.2.1.2
with the same results listed below).

Now I get this error when starting sysmond:

snmp.c:read_objid: Unknown Object Identifier (Sub-id not found: (top) -> 1)

And sysmon reports, for example:

Server: picard                             Current Time:  Oct 25 22:13:49 2005
Hostname                 Type  Port Count Notif Stat           Time Failed
--------------------------------------------------------------------------------
10.7.0.1              snmp  0    1     No    ERROR          Never

Stat eventually transitions from "ERROR" to "No Srvr Resp" even though
the host does repond to manual SNMP queries.

The identical configuration/software works on a development server,
but the production server is what is exhibiting the problem.

-michael