Taiwan's BenQ will soon be making dual-mode handsets supporting cellular technology and Wi-Fi, specifically using the Unlicensed Mobile Access (UMA) software of Kineto Wireless.

UMA allows hand-off a VoWi-Fi call to GSM and vice versa and is in trials with carriers like T-Mobile in the U.S., and many more over in Europe.

According to BenQ senior VP & GM Mobile Communication Business Group Dr. Irwin Chen, "Kineto's proven UMA client software and superior engineering support are helping BenQ accelerate our UMA products to market in order to meet the growing need for UMA handsets from our important operator customers."

No word on what carrier may support BenQ UMA phones in the future.

In October, T-Mobile become the first mobile operator in the U.S. to offer a dual-mode service. Through UMA, T-Mobile HotSpot @Home can seamlessly switch calls between a Wi-Fi and cellular connection; depending on which is available and most cost effective at a particular moment.

So a user can be on a cellular-call, using the minutes from their mobile plan, but when they walk into their home or in range of a T-Mobile hotspot, the call is automatically moved over to Wi-Fi; saving those minutes, without interruption.

T-Mobile HotSpot @Home, which is available now in Seattle on a trial basis, costs $20 a month on top of your regular cell phone plan. It delivers unlimited voice over Wi-Fi calls from T-Mobile's 7,000 hotspots and your home—through a Wi-Fi access point connected to your broadband Internet service.

T-Mobile is offering the dual-mode Samsung SGH-T709 slider and Nokia 6136 clamshell for the service.