With RIM's BlackBerry handhelds in danger of a shutdown for patent violations, Microsoft is ready to exploit the opportunity with its own push email offering.

The timing of the court struggle could help Microsoft, which has been manoeuvring its own Direct Push technology for email for the Pocket PC and smartphone market. Microsoft says the technology should be available by the middle of the year, making a head-first slide into a heated market.

IT managers using BlackBerry software are caught in limbo, worried they might suddenly not have a wireless email service, said Gartner analyst Monica Basso. Many enterprises plan to deploy more BlackBerry handhelds, and the litigation has thrown in doubt whether they should proceed or look at other options, she said.

"[IT managers] are supposed to keep providing high quality of service for their executives," Basso said. "They can’t afford to have it shut down overnight."

Microsoft is listening eagerly to those concerns. RIM's legal problems are "causing a lot of customers to come to us and ask about it", said Scott Horn, general manager for the mobile and embedded devices group at Microsoft, in an interview this week in London.

"It’s caused a lot of companies to say, 'Wow, mobile email is really important, messaging is very important, and it's an enterprise mission-critical thing for my company,'" Horn said.

NTP is seeking an injunction against RIM to shut down its BlackBerry service in the US. After NTP won its patent infringement lawsuit against RIM, an injunction was issued in 2003 but then stayed while the case was on appeal. An appeals court later upheld the infringement ruling.

On Monday, the US Supreme Court said it wouldn't review the dispute, and now a US District Court will decide on damages and whether to impose a permanent injunction against RIM. An injunction could shut down the sale of devices and services by RIM in the US.

That could force its push email customers to look for new products, and Microsoft, naturally, is willing to oblige.

A free upgrade for its Windows Mobile 5.0 software, called the Messaging and Security Feature Pack, is undergoing testing now by device manufacturers and mobile phone operators, Horn said. That upgrade – along with an existing upgrade for Exchange Server 2003 released in October – enables push email with Microsoft's software.

Devices equipped with the upgrade will ship in the first half of this year, Horn said.

Businesses are increasingly asking about deployment strategies and security issues with mobile devices, Horn said. Microsoft sees potential for large growth; the mobile email market stands at around 10 million users worldwide today, Horn said.

Microsoft has 130 million Exchange customers worldwide, Horn said, and it hopes to tap into that large base, as well as users of its other products, to promote its push email software. Most users carry mobile phones, he said, "and our strategy is to go to that customer base".

RIM's BlackBerry has been a trailblazer in the mobile email market, building a significant user base. But Microsoft's push email product will hold an advantage for customers using BlackBerry software on Windows Mobile devices with Exchange Server 2003, said Tony Cripps, wireless software analyst at Ovum.

Those users have a BlackBerry server between the devices and an Exchange server. With Microsoft's push email, the BlackBerry server could be eliminated, Cripps said.

However, he added, it will come down ultimately to how secure and manageable Microsoft's software turns out to be, and its total cost of ownership.

Microsoft has hedged its bets in case its customers don't embrace Exchange Server 2003 and an armada of Windows Mobile 5.0 phones updated for the push technology. It has licensed Exchange Server's ActiveSync protocol, which allows for synchronisation of email to other mobile phone vendors, Cripps said. "It would be silly to suggest that you can only access this service by Microsoft devices," he added.

Microsoft isn't the only company that could benefit from RIM's uncertain future.

Nokia and other users of Symbian's operating system have also been chasing the mobile email market. Last year, Nokia introduced a family of handsets targeting enterprise users, including one that looks similar to the BlackBerry.

Nokia also began selling software that supports push email, and is expected in the future to support remote access to other corporate data. That could complement services and software from Intellisync, the wireless email software developer that Nokia acquired last year.