Google Voice can be accessed from anywhere, but only after you set it up for the first time, and for the first time setup you need Google Voice to believe you are on the US; it also needs you to have a US number that if called you can answer and send DTMF.



For tricking it into thinking you're in the US when you aren't, the original instructions suggest using HotspotShield (instructions on how to use HSS with the N900 can be found at http://talk.maemo.org/showthread.php?t=66901 ); but that might not work, it gets in the way of answering the phone for me, the way i did it was to use TOR (with the statusbar menu applet), checking if my endpoint was in the US (with somthing like this for example), disconecting and reconecting till i got a US endpoint, there are some instructions on how to restrict the country for the endpoint out there but i didn't felt like following them.


Now the part about getting a US number is a tad more complicated. summing up what you will do is get a SIP account, set your N900 to use it, and link the SIP account to a US number.

Lets start with the SIP account creation and setting your N900 to use it:

* Go to http://serweb.iptel.org/user/reg/index.php and create your SIP account there

* After the account is created, you do the following to set your N900 to use it:

** Go to Accounts thru your favorite route, click new and pick SIP from the list and fill the parameters as described bellow (parameters not mentioned you leave at the default)

Address: yourusername@iptel.org
Password: your iptel pass
_____
Advanced settings
_____

Use for phone numbers: Unmarked
User name: the stuff before the @ in the address
Outbound proxy: sip.iptel.org


** After it is all set, see if it manages to sign in (if it doesn't, disconect HSS, and if you use Hamachi, turn it off), once signed in, you can test it by calling echo@iptel.org with that account and then making noises and listening for the echo if the call completes.



* Now to get yourself a US number, this part can be a tad annoying because some people didn't clear numbers they don't own anymore and GV won't let a number be registred more than twice.

** Go to http://phone.ipkall.com/ and fill the form like this:

Account type: SIP
Area code: pick any
SIP phone number: your iptel username (the stuff before the @iptel.org )
SIP proxy: sip.iptel.org
Email add. : your email address
Password: a password for that number


** Respond to the CAPTCHA challenge then hit submit and your new number will be sent to the email you specified


* Now in posession of your US number load Google Voice ( http://voice.google.com ) using whatever IP masking trick you prefer that doesn't get in the way of using your iptel SIP account, and proceed with the setup wizard, at step 3 of 4 you try inserting your US number.

** If GV complains there are already two accounts using that number, go back to ipkall and try for a new number (it would be polite to login with the number you can't use and delete the account to free up the number imediatly instead of letting it expire for lack of use)

* Once you got a number that is accepted you will be presented with two digits in step 4 of 4, memorise that number and hit the "Call me now" button, your N900 will ring from the SIP account (unless you set ipkall or the N900 itself incorrectly), answer the call then pull up the dialpad screen and press the two digits GV told you in sequence (there is no audible DTMF tone feedback, you will know if it worked by checking what GV is saying now)



___
This finishes the GV part of this tutorial, after doing this you should be able to use without IP masking from anywhere in the world. But GV only offers free calls for numbers inside the US



And this lead us to the second part of this tutorial, calling from the US to other countries for free:



To do this, you use GV to call for free to a number inside the US that will forward your call to international numbers for free.

I've spent several days trying to find one of those numbers that still offered the service, there used to be a lot of them but a mass extinction event has taken place, some did survive like 1800FREE411 but doesn't offer free intl. calls anymore; finally last night i found http://www.freephone2phone.com/

To call an international destination with it, using GV, you do it like this:


* Pick one of the many numbers it offers in that page and call it with GV


* Answer the SIP call on your N900

* Listen to the advertisement, then when prompted pull up the dialpad and press 1

* Listen to advertisement again and when prompted start dialing your intended intl. number, the format is just like the international format except you replace the "+" with "011"



Freephone2phone places no limit on the number of calls or of minutes per day, but they do limit the duration of each call, the first call to each number on the day can last up to 10 minutes each, any subsequent calls to a number you already dialed in the day can last up to 5 minutes each; but you can have as many free 5 min calls in a day as you can fit in 24 hours. The other limitation of freephone2phone is that for most countries they can only afford to offer free calls to landlines and not for mobiles.




________

I might have overlooked some important details, feel free to point where corrections are needed.



Sources:
http://www.levoltz.com/2010/03/04/un...ce-outside-us/
http://www.freephone2phone.com

does stuff like this break the TOS here

GV is US only by their policy, you are effectively posting directions to subvert restrictions they deliberately put on their service.

I tried ipkall, got a bad number, tried again, got the same bad number... maybe its a time thing, ill try again in the morning.

and I'm setting this up in preparation for my return to the US; others might do it before a trip abroad, many legitimate uses, methinks

try a different area code for your ipkall number

I'm not able to login to SIP. i've used the same settings you mentioned above.

I'm used TOR for IP masking. I tried to sign in both when connected to TOR(verified it was connected to US IP) and also when its disconnected. I tried after robooting my phone too. Ironically i'm not able to login even through my laptop with Xlite sip client..


Settings used in n900:

Address: userid@iptel.org
password: "password";

Advanced SIP settings:

Use for telephone number: Unchecked
Username: userid
Transport: Auto
Outbound proxy: sip.iptel.org
Port: 5060
Discover public address: Checked
Loose Routing: Unchecked
Keep-Alive mechanism: Auto
Keep-Alive period: Auto
Auto-Detect STUN: Checked



Settings used in XLITE4.0 in an Windows XP machine:

Accountname: Userid
Protocol: SIP (by default it was there not editable)

Allow this account for:
Call-Checked
IM-Checked

Userdetails:
Userid: userid
Domain: iptel.org
password: ************
displayname: userid
authorization name: userid@iptel.org

Register with domain name and receive calls: Checked

send outbound via proxy, Address: sip.iptel.org

Dial plan: #1\a\a.T;match=1;prestrip=2;


Please help me out.

Thanks in Advance
Hemanth

I have a dumb question, but how do you use GV from the phone?
I am in the US and I can just use my real phone number and no proxies. But thanks for the SIP tutorial, it's nice to have a real phone number that people can call me on my cellphone without having to pay anything.

@Radu: you can use google voice plugin or you can use dial central and make calls from it when you are connected to your 3g or wifi.

Hemanth147, can you login to your account in the iptel site itself?

yea.. i'm able to login to iptel.

XLITE 4.0 says: you are connected to internet through a firewall of type UNKNOWN NAT

I turned off antivirus, i gave an exception for XLITE in windows firewall but still i'm not able to connect.