The book that is Research In Motion (RIM) took an expected plot twist today, as Sprint has finally signed on to offer BlackBerry-based wireless e-mail and data access solutions on its Nationwide PCS (CDMA2000 1xrtt) network. It becomes the sixth major U.S. carrier to deliver BlackBerry support of one kind or another.

Sprint said it plans to make BlackBerry services, including "push" e-mail, appointments and contacts, available on select handheld devices and phones later this year. These devices could be RIM's own BlackBerry handhelds or any from the many third party device vendors and platform providers that are now compatible with its software platform. These include smartphones from Motorola, PalmSource, Nokia, Sony Ericsson, and Samsung.

By offering BlackBerry support, Sprint is aware it is playing catch up to the needs of its customers. The company's VP of Enterprise Marketing, Tim Donahue, said, "Sprint recognizes that the BlackBerry solution has a strong following with many enterprise customers, including government, financial and legal services. By combining this popular platform with the clarity and breadth of the enhanced Sprint Nationwide PCS Network, Sprint can provide an attractive wireless offering to better serve these customers."

With RIM BlackBerry, Sprint is bringing aboard the fastest growing mobile device platform. BlackBerries now account for 5.3 percent of the handheld market, growing an impressive 289 percent last quarter alone.