Please help with asterisk configuration

[jtk]

I did search all over and tried everything. I just can't make it work so I need some expert help.

First:
I port forwarded following ports to the asterisk machine
5060 UDP
10001-20000 UDP
4569 UDP

My asterisk sip.conf

[general]
context=demo
port=5060
;registerattempts=0
bindaddr=0.0.0.0
srvlookup=yes
disallow=all
externip=mywebsite.dyndns.com
fromdomain = mywebsite.dyndns.com
localnet=192.168.0.111 /255.255.255.0
canreinvite=no

register => 12345:PASSWORD@us.voxalot.com

[voxalot.com]
type=friend
username = 12345
fromuser = 12345
callerid =
secret = PASSWORD
host = us.voxalot.com
context=to_voxalot
qualify = no
registersip = yes
hassip = yes
hasiax = no
nat = no
canreinvite = no
hasexten = no
insecure = invite
allow=ulaw
allow=gsm

asterisk extension.conf

-- Skip Default & Demo config --

[to_voxalot]
exten => _8.,1,Dial(SIP/${EXTEN:1}@voxalot.com,20,r)


OK, after all tries, I thought my ISP (comcast) might have block the port 5060, I searched the web and I found out that it might be the case. (I can't confirm that if this is true for my ISP)

BUT what I can figure out is that, when I tried to connect voxalot with x-lite, it works!? of course I tested from the same network and asterisk machine. So does that mean the port is ok? I don't know.

btw I use ipkall for DID testing.

Please someone help me , thank you.