Not able to run snmpwalk for netscreen 5xp

[Chanchal Saha]

Hi,
I am having NNM 7.5 and a firewall netscreen 5xp, I am able to ping the interface but I am not able to run snmpwalk on this internal interface.It is giving me a timeout message.

Although I enabled SNMP Management on Netscreen and allowed port 161 & 162 and also allowed NNM host machine in the allow host machine, but still I am not able to run snmpwalk for this firewall.

I know that there is some configuration changes needs to be made in my firewall, but I do not know how to make this changes, can anyone help me out who is already having netscreen in place.