On the 5.2.x line, the "pass" extension
mechanism doesn't seem to handle SET
The command to invoke is constructed
successfully ("script -s OID type value")
but when script is actually called, it
doesn't see the value parameter.
This mechanism works correctly on the 5.3.x
line and above, which use different code
for invoking the extension script.
See the thread "passing parameters to a
perl script through snmpd" on the users list