SNMP - udpTable

I am implementing some of SNMP tables right now and I faced some misbehavior of SNMP agent.
udpTable from rfc 1213 doesn’t work properly. According to my understanding it should work like that:
udpLocalAddress. =
udpLocalPort. = 161
Istead of that the agent returns udpLocalPort. = 161 ( and no appearance of udpLocalAddress, lexicographically it stands before port, and why port index is zero?) and loops in it, so snmp walk is broken there. Definetely this is a bug and should be fixed.

Also I want to point out that agent hangs from time to time.

I use The Sierra Wireless AirLink™ Fastrack Xtend GPRS (former Fastrack Supreme 10)
Open AT Firmware V7.3.0.a.00
Open AT OS V6.21.02
WIP plugin V5.10.2020