zaptel.conf
fxsks=1-4 
defaultzone=us
loadzone=us

zapata.conf
[channels]

context=incoming
signalling=fxs_ks
callwaiting=no
callwaitingcallerid=no
threewaycalling=no
transfer=no
echocancel=yes
echocancelwhenbridged=yes
relaxdtmf=yes
rxgain=1.5
txgain=1.5
immediate=no
channel => 4

context=incoming
signalling=fxs_ks
callwaiting=no
callwaitingcallerid=no
threewaycalling=no
transfer=no
echocancel=yes
echocancelwhenbridged=yes
relaxdtmf=yes
rxgain=1.5
txgain=1.5
immediate=no
channel => 2

group=1

context=incoming
signalling=fxs_ks
callwaiting=no
callwaitingcallerid=no
threewaycalling=no
transfer=no
echocancel=yes
echocancelwhenbridged=yes
relaxdtmf=yes
rxgain=1.5
txgain=1.5
immediate=no
channel => 1

context=incoming
signalling=fxs_ks
callwaiting=no
callwaitingcallerid=no
threewaycalling=no
transfer=no
echocancel=yes
echocancelwhenbridged=yes
relaxdtmf=yes
rxgain=1.5
txgain=1.5
immediate=no
channel => 3