i have a case where NET-SNMP-EXTEND-MIB seems to be truncating args string. The arg string in this case is 500+. When i do a snmpwalk it seems to indicate that the whole string is taken but
the prog script seems to have truncated the string somewhere around 416.
To replicate, use NET-SNMP-EXTEND-MIB, extend a givne prog and provide args with string length more than 500.
What version of net-snmp?
Are you setting it up through snmpd.conf, or using snmpset?