Clicker, I'm in Canada and it worked for me.

heavyt, I just wanted to confirm whether the link you posted in step 6 should be prox01.sipphone.com or proxy01.sipphone.com

When I checked my Gizmo account for my sipphone number, it said @proxy, so that's what I used.

The calling part works fine; I can call my GC number through SkypeOut, and my N810 will ring (and thanks to the other helpful post, I now know how to press 1 to answer it!). So, that's all well and good. I have un-enabled my cell phone at GC because the whole reason for this set up is to avoid the crazy *** roaming charges of a Canadian cell phone in the US. But, when I tested it initially, both my N810 and my cell phone rang when I called my GC number.

My only issue now is when I try the "new internet call" and view the presence of my accounts, the GTalk is "connected" but the sipphone is "authentication failed." I suspect but I'm not sure that this is a router / "need to open a port" problem (as I have seen in some other threads) as I was having trouble connecting with just plain old Gizmo from the laptop. I haven't pursued the matter because I'm a SkypePro gal and that takes care of our outgoing calls.

But in summary, yes, heavyt's method works perfectly for my Canadian cell phone, and for receiving calls on the N810 in Canada.