Multiple users with the same SIP account

I have asterisk 1.4 and Openfire working together great with phone mapping on Asterisk-IM.

I want to be able to have the same SIP account mapped to two different users. For good reason, they share a phone and are always in the same room together. They never both need the phone at the same time. However, we want to know when one of them is on the phone, even if the other is not logged in to Spark.

When I attempt to map the same extension to two different users, I get an error saying that the device has to be unique. I am not sure I understand a technical limitation, since both should be able to subscribe to the status just fine. I’m looking for a workaround.

I know that version 1.4 of asterisk supports custom hints, and I’m wondering if I can get around this by creating an alias of some kind to satisfy Openfire’s desire for unique devices. The names of these hints are extensions, not devices - so I’m not sure I understand how I would do this.


user1@chat => SIP/100

user2@chat => SIP/100-1 (an alias of SIP/100)

Is this even possible? Or is there a conflict that prevents this from ever working?