This looks a lot like UMA to me: <a href="http://www.umatechnology.org/technology/index.htm" rel="nofollow">http://www.umatechnology.org/technology/index.htm</a><p>If that's the case, T-Mobile US has UMA working already. Caveat: you need a special WiFi router so the cellphone gets good battery life on WiFi.<p>Does anyone know what Cherry is using?