Updated

Research In Motion's (RIM.TO) Blackberry will remain the standard for mobile email in the face of a challenge by Microsoft and Nokia (NOK), whose rival email systems aren't as cheap or secure as they claim, RIM's CEO said on Monday.

"It's insecure. And Microsoft and Nokia use about five times more of the network than we do. Network capacity is scarce and battery power is scarce. That's why operators can price BlackBerry aggressively," RIM Chief Executive Jim Balsillie said in an interview at the fringes of 3GSM, the world's largest wireless trade show.

Initial launches by mobile operators indicate that the offering from Microsoft is indeed priced in line with that of BlackBerry, at around $30 a month, despite Microsoft's initial claims that push, or mobile, email would become virtually free of charge.

"They [the operators] are pricing it pretty much the same," confirmed Pieter Knook, senior vice president for the mobile and embedded software division at Microsoft (MICR).

Microsoft denies, however, that its push email service is insecure, saying it has the same security features of Outlook Web Access used by many of its customers.

Balsillie reiterated that a technical workaround which his company announced late last week will ensure the BlackBerry service continues uninterrupted even if a U.S. court grants an injunction requested by patent holding company NTP Inc. to halt the email service.

"There won't be an interruption of the service. Our 3.5 million users in the United States won't have to do a thing. They will continue to receive their emails," he said.

MOBILE EMAIL JUST STARTING

Blackberry is used by around 4.5 million subscribers around the world, including some U.S. government staff.

Microsoft and Nokia are eyeing the hundreds of millions of workers and consumers who want access to their email wherever they are. In recent months, both companies have started offering cheap server software that pushes email to mobile devices.

Microsoft said on Monday four big operators, Vodafone (VOD.L), Orange (FTE.PA), T-Mobile (TMOG.UL) and Cingular, would retrofit a number of mobile handsets running on Windows Mobile software so they can start receiving this "push email" on their pocket devices. New Windows Mobile devices can automatically receive push email.

Microsoft targets tens of millions of enterprise customers who use its Outlook 2003 email system, which can start forwarding email to mobile devices after a free software upgrade.

Nokia, however, must first sell an additional new email server to enterprises.

But RIM said its rivals' focus on pushing wireless email only from their own servers to their own devices is their key shortcoming.

"We support multiple email systems on devices from many different vendors to consumers and enterprises," Balsillie said.

He also stresses that while its rivals are just launching an email product, RIM has already moved on from mobile email to a range of other wireless services, such as SAP (SAPG.DE) enterprise applications and Google maps (GOOG).

"Internet is passe. Nokia management says it's just about a keyboard on a mobile phone. Are enterprises looking for a knock-off product, or are they looking for an interactive platform? Why all the attention to only a small part of the market while we service all of it so well," Balsillie added.