From CSCul33490 - No release planned to fix this bug and There's no way to get the phone to use the time from an NTP server on the affected firmware versions. Also that bug report tell us that The phone will sync with the timestamp in the 200 OK response to the REGISTER from the Cisco Unified Communications Manager (CUCM) server it registers with. If I don't use a CUCM can I use something like Scapy tool for packet crafting and recreate this REGISTER with this 200 OK timestamp? If it's possible - can someone provide me an correct .pcap captured near CUCM server for recreating this packet in correct form?
Thanks in advance for any help.
Best regards
Kosintsev Alexander