By Aidan Malley

Published: 10:05 AM EST

As much as Research in Motion is keen to maintain its marketshare edge against Apple, a new internal job listing suggests the BlackBerry creator is willing to jump the fence and write applications for the iPhone.

People familiar with the listing say the Waterloo, Canada-based smartphone designer is distributing the notice only within the company and is keeping most details hidden even to those aware of the posting.

"As part of a newly-created team, you’ll influence the development and design of BlackBerry software," the listing reads. "This is a very confidential brand new team and a senior position within RIM so I can't provide too many details. I guess you can figure out what it might be about though."

Among the requirements are a very strong emphasis on existing experience with Mac development, including programming in both Cocoa and Objective C as well as user interface design.

Web experience with Javascript, XML, and other functions is also essential. Experiences with developing for the Mac's Sync Services feature and interfacing with Bluetooth and USB devices are both considered assets, according to the company.

The level of secrecy is unusual for RIM, which has seen repeated leaks of its 3G-capable BlackBerry plans as well as brief discussion by company executives of its near-term releases. Some as yet unverified reports have alluded to a touchscreen BlackBerry that would directly compete with Apple's handset.

What RIM's intentions are for the new development team, and any iPhone applications that may result, is unclear. While often protective of the BlackBerry's distinctive "push" service that delivers e-mail in real time, the company has allowed rival phone builders such as Samsung to access its mail system and integrate its SureType input method into their software.

Still, any development for the Apple platform would represent an unusual move for the Canadian firm, which analysts have said may lose marketshare in the US once native third-party applications and Exchange data support allow business users to rely on the iPhone.

RIM would stand as just one of hundreds of high profile firms who've recently signed on to develop applications for the touch-screen handset. During a recent conference call with analysts and members of the media, Apple said that over a third of companies in the Fortune 500, and over 400 higher education institutions, have applied for iPhone developer status since last month.