Trunk to App

I have an application like

exten => 12001,1,Answer()
exten => 12001,n,…

if internaly i press 12001, aplication run perferct
what i need is as soon on any/did/etc trunk receive a Call.
i want to call that application.
what should i do?

any idea?

Thank in advanced for any kind o help.

Put the context of your application in the trunk. Use the ‘s’ option in your extensions.