MGCP Phone start process (chan_mgcp.c)


I currently try to modify chan_mgcp.c to make it works with LG-Nortel phones.
I can make it rings, hangup etc but there is still a trouble: the phone asks to asterisk to restart every 3 secondes, I think because the phone doesn’t receive the right message.

Does anyone knows which message is telling that the phone is connected ?

Thank you