[Asterisk-Users] Changing caller ID based on the extension dialled?

[Remco Barende]

Hi list!

I am going to install an intercom module for our home. The intercom can 
cater for 3 doors where people can ring the doorbell and the unit can 
also remotely open the door (Siedle system).

It would be nice however to know that you are opening the right door or at 
which door the people are ringing.

For each door I am able to program a different extension that will be 
dialled. Can I have asterisk change the Caller ID that will be displayed 
on the phone based on the extension that is dialled? The call will always 
be from one telephone line(extension) so this is no option.

I want it like this:

Door:		Extension dialled	Phone display (CID)
Front		301			Front door (or 301)
Garden		302		 	Garden door (or 302)
Gate		303			Gate

I guess that this is the opposite of what Caller ID was meant for but it 
would suit the job that well :)

Thanks!!