thanks Mike. Here is what I have "discovered" and might be of help to others:

1. Sometimes if your Nokia never connects to the internet, shut it off, take out the battery and after 60 seconds start the cell - you will be connected with full signal.
2. Because of the wi-fi feature, the cell phone uses up a lot of power. When the power is low, the wi-fi switches off.
3. T-mobile requires the call to be initiated through the wi-fi. The call keeps switching between the wi-fi network and the t-mobile mobile coverage, but the call is still treated as @home.

4. This technology is new, but T-mobile has been very bold in using this and being the first to use it in the US.

5. If you are short of minutes, then if you receive a call, then you can put down the phone and call back after ensuring that the call is through the wi-fi network. Often when a call comes, the in-coming call is through the t-mobile tower, especially if you live in a house with 2 or more levels.

6. I used a wi-fi booster. This does not work well with the Nokia phone. It still talks to the router wi-fi base only. So, the only remedy is to keep the wi-fi router in the floor you use the cell phone the most.

I use this phone but my wife has it today so I can't check settings. I do know that the upper left of the main display should display the router name in red when you are on the wifi instead of the cellular network.

I don't know off the top of my head how to force wifi connect but maybe the router can be placed closer to the stairs, near a window (if the basement has one), higher in the room, and try moving the router's antennas around to try and get a stronger signal to the phone. I use the same router (but probably different firmware) and not only do we get full coverage throughout our second floor two bedroom condo, we also get coverage by the pool and barbecue, though the pool area is below the back bedrooms. The router is by a big sliding door window in the front room, so we're at what should be the edge of wireless coverage for the router (100 - 150 feet). Not only does the phone hook up but my Palm t|x and hp dv6120 laptop do as well. I also use WPA and only allow my devices' (and some friends' devices too) MAC addresses to access the wireless but that should not affect coverage.

My mom got a Nokia 6086 with the @home service using their existing linksys router system. The router is in the basement and level 1 and level 2 has wireless coverage. She made calls to me yesterday and only a few calls made from level 1 showed up as U (at home through the internet), others showed up as normal calls made through the T-mobile cell tower. The calls switch seamlessly between the internet and the t-mobile wireless tower.

Is there a way to force calls on the Nokia 6086 only through the home Wi-Fi network? Would a buying a "Linksys - RangePlus Enhanced Wireless-MIMO Router with 4-Port Ethernet Switch WRT100" or some other wireless router help?

It is frustrating to think that one can have free unlimited calls through the home Wi-Fi and realize later that the calls are being charged. I would really appreciate your feedback if you have worked how to overcome this problem.

thanks!