[Asterisk-Users] Can you invoke an app before dialtone?

[Dave Packham]

say I needed to send a broadcast message that I wanted every user to
hear when the pick up thier phone?  can I "Play,message" on a line just
before they get dialtone?  or maybe after they dial before ring?  how
about a "ringdown" to a voicemail box and on end return them to thier
line for the dialout?   can * do ringdowns?  when a user picks up an
extension it automagically rings an extension?


Dave