asterisk users - May 2007 - Call waiting / hook flash on ZAP trunk from SIP phone?

Hello.

After doing much web searching and searching archives of this mailing 
list, I see that my question has been asked at least 6 separate times 
but no answers have been attached.

In a nutshell, is there a way for a SIP phone to easily hook flash a ZAP 
analog trunk mid-call? (This is important when trying to make use of 
features on a PSTN analog line such as call waiting, call forwarding, 
3-way calling, etc.)

I've seen the *3 trick (mentioned in the comments here 
http://www.voip-info.org/wiki/index.php?page=Asterisk+cmd+Flash ), but I 
don't know in which context to put the extensions.conf stuff:

exten => s,n,Set(DYNAMIC_FEATURES=zapflash)
exten => s,n,Dial(SIP/xxxx,15,tw)

...to make it take effect while on a call.

My configuration:

- 1 X100P card with one analog line attached with call waiting, caller 
ID, 3-way calling enabled on the line.
- 1 Snom 300 SIP desk phone

My Zapata.conf:

[trunkgroups]
; define any trunk groups

[channels]
; hardware channels
; default

usecallingpres=yes
usecallerid=yes
cidstart=ring
cidsignalling=bell
callwaiting=yes
callwaitingcallerid=yes
threewaycalling=yes
transfer=yes
cancallforward=no
callreturn=no
immediate=no       ; for Caller ID, allows time for telco to send digits
hidecallerid=no
echocancel=yes
echotraining=yes
useincomingcalleridonzaptransfer=yes
context=from-pstn       ; Incoming calls go to [from-pstn]
signalling=fxs_ks       ; Use FXS signalling for an FXO channel
group=0			; Use with Zap/g0
channel => 1            ; PSTN attached to port 1


Thank you very much for your time. Hopefully we can get an answer to 
this and put it on the Wiki for all to see!

Sincerely,
Sean M. Pappalardo

<<--------------------------------------------------------------------------------->>
This E-Mail message has been scanned for viruses
and cleared by >>SmartMail<< from Smarter Technology, Inc.
<<--------------------------------------------------------------------------------->>