[cisco-voip] Unity 4.2(1) Dial by Extension Failures

[Carter, Bill]

I have a Unity 4.2(1) vm-only system with 2,000 subscribers. We are
occasionally getting reports that when an outside caller reaches the
Unity Auto-Attendant, they enter the extension of a subscriber and get
the Unity error "I did not recognize that as a valid entry".

Seems like when this occurs it happens multiple times. In testing they
enter the extension, get the error, re-enter the extension, still fails.
They can hangup, call in again and get the same error. 10 minutes later
Unity accepts the extension.

I have checked the voice gateways, all the VoIP dial-peers have
"dtmf-relay h245-alphanumeric"

What can I setup in Unity to log/debug when this happens?

Thanks,
Bill