With IPHost Network Monitor you can run simple snmp requests against a Cisco device in your network.
cSipCfgReasonHeaderOveride
Cisco Sip Configure Reason Header Overide
1.3.6.1.4.1.9.9.152.1.1.1.15
This object specifies that the Reason header overrides SIP status code mapping table.
Back to CISCO-SIP-UA-MIB MIB page.
IPHost Network monitor allows you to monitor cSipCfgReasonHeaderOveride on Cisco device via the SNMP protocol. Download IPHost Network Monitor (500 monitors for 30 days, 50 monitors free forever) to start monitoring Cisco firewalls right now.