zaptel.conf:

#
# Zaptel Configuration File
#
# This file is parsed by the Zaptel Configurator, ztcfg
#

# channel 1 is an fxs port (therefore uses fxo signaling) connected to a multi-line analog phone
fxoks=1

# channels 2-4 are fxo ports (therefore use fxs signaling) connected to the PSTN through analog trunks
fxsks=2-4

# default indications as US
loadzone=us
defaultzone=us


zapata.conf:
[trunkgroups]
; define any trunk groups

[channels]
; hardware channels
; default
usecallerid=yes
hidecallerid=no
callwaiting=no
threewaycalling=no
transfer=yes
echocancel=yes
echotraining=yes

; channel 1 is an FXS port connected to an analog multi-line phone (and thus uses FXO signaling)
context=ael-internal
signaling=fxo_ks
channel => 1

; channels 2-4 are FXO ports connected to the PSTN (and thus use FXS signaling)
; define channels
context=ael-incoming
signaling=fxs_ks
group=1
channel => 2-4