Sign up for Gizmo Project (www.gizmoproject.com).
Configuration steps:
1) In Tools -> Settings -> Connection -> SIP settings ->Create the
following profile
Profile Name: sipphone
Service Profile: IETF
Default Access point: [your WLAN AP name]
Public user name: sip:
[email protected]
Use Compression: No
Registration: "Always on"
Use Security: No
--
Proxy Server: sip: proxy01.sipphone.com
Realm: proxy01.sipphone.com
User Name: 1747xxxxxxx
Password: [You SIPPhone password]
Allow loose routing: Yes
Transport Type: TCP
Port: 5060
--
Registrar Server: siproxy01.sipphone.com
Realm: proxy01.sipphone.com
User Name: 1747xxxxxxx
Password: [Your SIPPhone password]
Transport Type: TCP
Port: 5060
Registration: "Always on" and "When needed" is the switch to turn on
and off SIP registration. So typically when I'm configuring I choose
"When needed", and after I have done all the 3 steps, I come back here
to change to "Always on" to switch on SIP registration.
Transport Type: TCP is a bit surprise for me, but UDP didn't seem to
work. That's one of those tried and working thing.
2) In Tools -> Settings -> Connection -> Internet Tel. Settings ->
Create a new profile for "sipphone"(1747xxxxxxx), name it "sipphone"
3) In Connectivity -> Internet tel. -> Preferred profile -> Choose "sipphone"
At this point you might need to do the previous mentioned step: change
Registration to "Always on" in "SIP settings". The phone should now
start to get WLAN association, with a fat WLAN icon on top right
screen indicating success. Then it will take a little while to
register to the sipphone.com, after which a small Internet call icon
will appear next to the fat WLAN on icon. Voila! Now you are
registered and ready to make calls!
(Special thanks to Dameon for providing this information)
I copy/paste the above for HOFO from: http://support.gizmoproject.com/index.php?_a=knowledgebase&_j=questiondetails&_i=207