Play a message when destinate answer

hello to all

i have a sip trunk with 4 fxo port’s.i have a message,and i want when i dial out with sip trunk and my called number call pick up,hear my message.

note:i dial destination number custom.just i want when he answered.just hear my message.

please help me and tell me how i can do it.

thanks

See if this helps:

http://www.voip-info.org/tiki-index.php?page=Asterisk+auto-dial+out