Nokia says it will have overcome problems of short battery life in multi-radio handsets to deliver its first dual-mode Wi-Fi-enabled 3G phone before the end of this year. However, smooth call handover from wireless LANs (WLANs) to cellular networks is not yet assured.

Wi-Fi-enabled mobiles could save firms money by routing calls through the nearest available wireless LAN. This could help to avoid expensive cellular tariffs, while allowing IP calls to be made over the internet through 3G connections when out of Wi-Fi range.

Mahmoud Dasser, senior manager for Cisco's mobility partnership and operations, said problems still had to be solved to hand over calls without either dropping the connection completely or introducing significant delay into conversations. "Cellular-to-wireless handover is a work in progress," he said.

Nokia director of technology marketing Seppo Aaltonen said telecoms operators will not worry about losing revenues from calls switched from cellular to enterprise networks, given that improved indoor coverage and greater use of mobiles in offices will provide them with more enterprise subscribers. "There will be more mobile handsets within the enterprise, while operators will also host IP PBX Centrex services for firms that cannot afford their own systems," he added.

Markku Rauhamaa, Nokia's vice-president of wireless network solutions, argued that replacing mobile and desktop phones with series 60 Nokia smartphones could make IT management easier.