I am trying to configure the Tandberg E20 with CUCM 7.0.1. I have it configured as an advanced SIP endpoint. I have verified that partitions and CSS are correct. I can call from a SCCP IP phone to the Tandberg, but cannot make any calls from the Tandberg E20 to the SCCP phones. The Tandberg just says 'connecting to XXXX', sits there for a period of time and then comes back with a 'call cannot be connected' message.
I have seen this posted before, but couldn't find what the fix or possible issue was.