Since most Dialing Options act on the called party, not on the caller, you should get a little creative. It's a little weird to do such things to the caller, not the callee, but hey, this is Asterisk: there is usually a way to do what you want.
- ( ) G. :
, .
, G / - - . , Bridge. Dialplan (: , , ):
[default]
exten => 1000,1,NoOp()
same => n,Dial(SIP/alice,,G(default^bridge_and_play^1))
same => n,Hangup()
exten => bridge_and_play,1,Goto(jump_caller,1)
same => n,Goto(jump_called,1)
same => n,Hangup()
exten => jump_caller,1,NoOp()
same => n,Answer()
same => n,Playback(tt-monkeys)
same => n,Bridge(${bridge_this})
same => n,Hangup()
exten => jump_called,1,NoOp()
same => n,Set(MASTER_CHANNEL(bridge_this)=${CHANNEL})
same => n,Wait(1000)
same => n,Hangup()