This is a question that all of us have pondered at one time or another. It must be stressed that the balance between Privacy and Call coverage is tough with all CCM versions until CCM 5.X
Unfortunately when you use Shared Lines with CCM versions before 5.x this is expected behaviour :( This is one of the biggest drawbacks of using Shared Lines (all call details are passed along with each call).On CCM the feature you want BLF (Busy Lamp Field)is not available until CCM 5.0(1). This is a feature that was much requested on releases leading up to 5.0 Have a look at the following link. Here is an excerpt;
When you configure Presence in Cisco CallManager Administration, an interested party, known as a watcher, can monitor the real-time status of a directory number or SIP URI, a presence entity, from the device of the watcher.
A watcher can monitor the status of the presence entity (also called presentity) with the following options:
Missed call, placed call, or received call lists in the directories window
A Phone Monitors a BLF/SpeedDial.
After an administrator configures the presence feature and the BLF/SpeedDial buttons, a user can immediately begin to monitor the real-time status of a presence entity.
SIP traces provide key information in troubleshooting SIP Trunks, SIP
endpoints and other SIP related issues. Even though these traces are in
clear text, these texts can be gibberish unless you understand fully
what they mean. This document attempts to br...
Please find the attached HTML document, download and open it on your PC.
This provides an easy to use form where you simply answer a few
questions and it will render the proper jabber-config.xml file for you
to copy/paste. There is built in logic to verif...
CUCM Database Replication is an area in which Cisco customers and
partners have asked for more in-depth training in being able to properly
assess a replication problem and potentially resolve an issue without
involving TAC. This document discusses the bas...