My strong suggestion would be to
Upgrade 412 and all mods to 1.4(25)
Make sure the version of VM is correct being 1.4.3
In my experence I have seen many sites reboot, and do strange things because of the version or incorrect version of VM being run .
When you have done this you are dealing with a level paying field, and I would perform your tracing again and post the results it it continues to reboot.
The options that should be ticked in manager are
• Call/Packets/Line Send
• Call/Packets/Line Receive
• Call/Packets/Extension Send
• Call/Packets/Extension Receive
• Call/Packets/Extension RxP
• Call/Packets/Extension TxP
• Call/Events/Call Delta
• Call/Events/Map
• Call/Events/Targetting
• Call/Events/Call Logging
• System/Error
• System/Print
• System/Resource Status
Also it would be hard to get support from AVAYA as they will ask for the VM to be upgraded and for you to be running 1.4(25)
Certain versions of 1.3 were very unstabale in regard to conferencing on the 412 and would cause rebooting. The upgrade precedure from 1.3 to 1.4 is very stright forward, if you are going to go down this track re-post and i will give you the main steps.