Microsoft will use this week's 3GSM World Congress in Barcelona to unveil new Windows Mobile handsets and push its vision to better integrate the mobile world with today's business IT infrastructure. And both Microsoft and Symbian will disclose separate plans to put their respective software platforms on lower cost phones.

During his keynote speech, Microsoft chief executive Steve Ballmer is expected to talk about the opportunities for carriers to build new services around messaging, and how to integrate mobile devices with the communication services in today's Windows PCs.

A key theme will be lowering the cost of devices and services, which are currently barriers to wider adoption by businesses, according to John Starkweather, group manager for Microsoft's mobile and embedded division.

"Businesses want to manage mobile devices just like they do a PC. Why should they need special infrastructure, like a dedicated messaging server?" he said.

Microsoft will also detail how it has been working with Texas Instruments to enable lower cost handsets by running Windows Mobile and the wireless stack on a single processor. This can lower the build cost by thirty per cent, according to Microsoft. Feature phones using the design could ship within the next 12 months.

Meanwhile, Symbian has announced its own reference design for single-core 3G handsets and a new pricing model to reduce license fees for phone makers. Both moves should lead to less costly Symbian OS handsets.

The 3G reference design springs from collaboration with Freescale Semiconductor and Nokia, and is expected to cut handset development time in half, Symbian said.

On show at 3GSM will be the first Windows Mobile devices with built-in support for the Direct Push technology in Exchange Server 2003 SP2. These include HP's hw6900 Mobile Messenger and the Pocket Loox T Series from Fujitsu-Siemens.

Both are feature-rich devices with support voice and data over GPRS, built-in GPS navigation, Bluetooth and Wi-Fi, plus a Qwerty keypad for messaging. The Pocket Loox also boasts 3G wireless and VoIP support. Both vendors plan to ship the devices in versions with and without a digital camera.

Existing Windows Mobile 5.0 devices can be upgraded with push email support via a firmware update from network operators or handset makers, Microsoft said.