[VoIP] Seize zap channel without dialing

[Donald Froula]

I wonder if anyone knows how to do accomplish the
following.

I want to be able to seize one of my SF/MF Zaptel
trunks without dialing any digits.

I normally route a call through my T1-Over-Ethernet
trunks with a simple dial command like:

exten => 2600,1,Dial(ZAP/g1/999)
exten => 2600,2,HangUp

This dials extensions "999" through the SF/MF trunks,
and allows the blue box user to seize the ringing 999
extension with 2600.

I want to be able to simply seize the line without
dialing anything, allowing the user to "stack" calls
without having to blow 2600 and release the entire
stack. Just seizing the trunk on connecting would
allow the blue box user to simply outpulse the MF
digits within the trunk timeout window (5 seconds or
so), similar to the Phonetrips "classic tandem
stacking" recording.

I tried omitting the extension:

exten => 2600,1,Dial(ZAP/g1/)
exten => 2600,2,HangUp

This doesn't work, since KP-ST with no digits still
gets sent, routing the call do the default extension
in my incoming trunk context.

I hope this all makes sense.

Any ideas?

Don