Yeah it can do that minus the Caller ID display part. I have a basic Nokia CK-7W Bluetooth Handsfree kit in the car (one little button controls it). The speaker output is plugged into the Empeg AUX and the 'Phone Mute' line is connected up. Phone rings, Empeg+Hijack switches to Aux, ringtone through the speakers, caller name announcement through the speakers (Nokia S60). Press the button, have conversation, end of call it switches back to what it was doing before.
Even works when the Empeg is in standby. I should really YouTube it for you guys who haven't seen it at an Empeg meet.