Microsoft has also announced an alliance with Texas Instruments (TI) to produce a high-performance computer chip that could cut prices of Windows Mobile-based "smartphones" by an estimated 20%.
TI's new single-core chips "offer significant savings on the total bill of materials," Microsoft said in a written release on Monday.
Edgar Auslander, general manager of worldwide strategy for TI's wireless business unit, said:"Texas Instruments' integrated and optimised (chip) was designed to deliver enhanced features at a reduced cost."
He said: "Combined with Windows Mobile software from Microsoft, the (chip) will enable handset manufacturers... to bring advanced multimedia and productivity features to mainstream mobile phones."
The new handheld devices should be available within 12 months, according to Microsoft.
The promise of inexpensive wireless telephone, e-mail and data devices accompanied word that businesses using Microsoft Exchange 2003 operating system can "direct push" company e-mail to mobile telephones already on the market.
The moves came as a US judge was poised to rule whether to block Research In Motion (RIM) from providing its BlackBerry e-mail-forwarding service in the United States because it violated a patent by the US company NTP Software.
A major cell phone conference is
on at Barcelona in Spain
The announcements were timed to coincide with a major mobile technology conference in Barcelona, Spain, and not to capitalise on RIM's legal misery, Microsoft spokesman Mark Burfeind told AFP.
Burfeind said: "Microsoft's game plan is to be more cost-effective and offer more choice to customers. It has nothing to do with the patent-infringement lawsuit."
Mobile networks Cingular Wireless, Orange, T-Mobile and Vodafone immediately announced free upgrades to let Windows Mobile 5.0 customers reflect e-mail from company servers to wireless devices.
A set of handheld makers unveiled new wireless devices tailored to the Microsoft Mobile system.
Kevin Dallas, general manager of Microsoft's Mobile and Embedded Devices Division said: "Our mobile operator partners are eager to expand their customer base with a diverse and affordable portfolio of Windows Mobile-based devices."
"Texas Instruments' innovative hardware platform, coupled with our software, will help device-makers sell more smartphones to an increasing number of mobile workers who want to stay connected while away from the office."
The coordinated announcements signalled a major push by Microsoft to unseat RIM's BlackBerry as reigning wireless e-mail device.
RIM's handheld device is reportedly used by more than three million people in the United States.
RIM said last week it has developed a "software workaround" to maintain US service even if a judge enforces an injunction later this month as requested by NTP in the patent infringement case.
"Microsoft's game plan is to be more cost-effective and offer more choice to customers. It has nothing to do with the patent-infringement lawsuit"
RIM and NTP were reportedly negotiating but had yet to come to terms.
RIM said its latent software patch has been tested and pre-loaded into new handsets, ready to activate if it loses its battle with NTP, and can be downloaded into older Blackberries.
NTP sued RIM for patent infringement in 2002 and won an injunction the following year to shut down the wireless e-mail service in the US.
The injunction was delayed pending appeals.
The US Justice Department has filed a brief in the case seeking an exemption from any injunction for the estimated one million government users of the BlackBerry.