sip.conf:

[general]
context=default
srvlookup=yes
videosupport=yes
externhost=svartalfheim.homeunix.net
externrefresh=10
nat=yes
canreinvite=no
localnet=192.168.0.0/255.255.0.0
register => 863638:XXXXXX@fwd.pulver.com

[fwd]
type=friend
secret=XXXXXX
username=863638
fromuser=863638
host=fwd.pulver.com
fromdomain=fwd.pulver.com
disallow=all
allow=gsm
allow=ulaw
allow=alaw
context=incoming
tos=reliability
insecure=very

[1001] ;IPKall
type=friend
dtmfmode=rfc2833
context=incoming
host=66.54.140.46
tos=reliability
insecure=very
nat=no

rtp.conf:

[general]
rtpstart=10000
rtpend=10500