I'll be in Canada for a little while and wanted to arrange a way for my elderly mother to call me easily from New York. I had the idea of adding my Canadian hotel-room's direct number to a Google Voice account. That way my mother could dial a local New York number and reach me in Canada. She refuses to touch computers, but this seemed to be a way to access free VoIP, US to Canada, using actual phones. Calls between the US and Canada are free on Google Voice this year (2012), so there should be no trouble, right?
But it's not permitted. The Settings page will not allow me to add a Canadian number to an account that is already associated with a US number. The actual error is "Country of the forwarding phone does not match the user's country."