Question on vpnc-script-win.js Script

[Steven Petraglia]

I'm trying to set a route on the Client side after a connection is made.
If I manually do a:
  route add n.n.0.0 mask 255.255.0.0 192.168.1.1 Metric 1 IF 12,
it routes thru my Wireless card (IF=12) and bypasses the tunnel.

I want to do the same thing in the script.
I can use the 'gw' variable for 192.168.1.1, but where do I get the 
(pre-connect) Interface from?

- Steve