snmpset is failing on usmDHParameters.0 OID

Hi,

I need your help regarding the snmp-set operation against the scalar OID usmDHParameters.0

This OID is defined in SNMP-USM-DH-OBJECTS-MIB.txt and the object defintions as follows

################################
usmDHParameters OBJECT-TYPE
    SYNTAX  OCTET STRING
    MAX-ACCESS read-write
    STATUS  current
    DESCRIPTION
        "The public Diffie-Hellman parameters for doing a Diffie-Hellman
    key agreement for this device.  This is encoded as an ASN.1
    DHParameter per PKCS #3, section 9.  E.g.

        DHParameter ::= SEQUENCE {
           prime   INTEGER,   -- p
           base    INTEGER,   -- g
           privateValueLength  INTEGER OPTIONAL }
################################
SNMP-GET Command is successful

[root@mahesh usmDHParameters]# snmpget -v2c -c wimax 10.201.114.135 usmDHParameters.0
SNMP-USM-DH-OBJECTS-MIB::usmDHParameters.0 = Hex-STRING: 30 81 87 02 81 81 00 FF FF FF FF FF FF FF FF C9
0F DA A2 21 68 C2 34 C4 C6 62 8B 80 DC 1C D1 29
02 4E 08 8A 67 CC 74 02 0B BE A6 3B 13 9B 22 51
4A 08 79 8E 34 04 DD EF 95 19 B3 CD 3A 43 1B 30
2B 0A 6D F2 5F 14 37 4F E1 35 6D 6D 51 C2 45 E4
85 B5 76 62 5E 7E C6 F4 4C 42 E9 A6 37 ED 6B 0B
FF 5C B6 F4 06 B7 ED EE 38 6B FB 5A 89 9F A5 AE
9F 24 11 7C 4B 1F E6 49 28 66 51 EC E6 53 81 FF
FF FF FF FF FF FF FF 02 01 02

My question is snmp-set is failing on this object even though set operation is defined for this object (ie OID is read-write type). Can you please provide any inputs?

snmpset -v2c -c wimax 10.201.114.135 usmDHParameters.0 x 0xFFFFFFFFFFFFFFFFC90FDAA22168C234C4C6628B80DC1CD129024E088A67CC74020BBEA63B139B22514A08798E3404DDEF9519B3CD3A431B302B0A6DF25F14374FE1356D6D51C245E485B576625E7EC6F44C42E9A637ED6B0BFF5CB6F406B7EDEE386BFB5A899FA5AE9F24117C4B1FE649286651ECE65381FFFFFFFFFFFFFFFF

I tried with other options -> s "ox111...", x "0xfff11.." and etc with snmpset


ERROR is :

Error in packet.
Reason: wrongValue (The set value is illegal or unsupported in some way)
Failed object: SNMP-USM-DH-OBJECTS-MIB::usmDHParameters.0

Regards,
Mahesh