[Asterisk-Users] Confused of London - How to associate zap channels to extensions

[Asterisk]

I was playing around with the Flash Operator Panel, and came smack into a 
brick wall.

We have a * box linked to a legacy Meridian System using a EuroIDSN link 
(TE405p) with 10 channels enabled. I also have several SIP extensions.

What I wanted to do was to have a button for each of our (say) 32 users, 5 
of which are on SIP. That leaves the other 27 on Zap. A potential of 27 
users on 10 channels doesn't go, but we rarely have more than 8 channels in 
use at any one time.

Now, I can define a button for each of the SIP extensions easily. But how do 
I do the same for the ZAP extensions, as the zap channel number may be 
different each time a call is made to that extension ?

In my extensions.conf, I simply dial the zap extension using the zap group 
DIAL(zap/g1/4321)

Julian.