Cisco multiple extensions

I’m trying to get multiple extensions on one Cisco 7970 worked out.

Currently, the phone is registering correctly for both extensions I have configured for it, but when an incoming call comes in, it does not discern which extension it’s coming in on and shows it coming from the first line.

I have verified that Asterisk is passing the correct extension to the phone. Also, if I make a call OUT from the Cisco, and choose the line I want to send it out of, it works fine.

Incoming calls is where I have the problem.

Any ideas? It happens with the 7960 series as well. I’m thinking this is just a bug or shortcoming in the SIP code on these phones.