asterisk users - Sep 2008 - Dialplan terminates when the caller hangs up

Hi,

I've tried the following toy dialplan:

[sipcalls]
exten => _X.,1,NoOp()
exten => _X.,n,Dial(SIP/${EXTEN},,g)
exten => _X.,n,Playback(good-bye)
exten => _X.,n,Hangup()

With the above dialplan, when the callee hangs up, Asterisk does play
"good-bye" to the caller. However, when the caller hangs up, the
dialplan seems to be terminated immediately without playing "good-bye"
to the callee.

Is it possible to do somethings so that the dialplan continues after the caller
hangs up?

Cong-Van