(Adds CEO quotes, details, background. In U.S. dollars unless noted)
By Wojtek Dabrowski
TORONTO, Dec 20 (Reuters) - BlackBerry maker Research In Motion Ltd RIM.TORIMM.O reported a third-quarter profit that beat expectations on Thursday, sending its shares higher even as it delivered a subscriber outlook that fell short of analyst predictions.
The smartphone designer also continued to diversify its client base beyond the corporate and government clients that have been its mainstay. At the end of the quarter, non-enterprise customers made up 34 percent of its subscriber base.
RIM earned $370.5 million, or 65 cents a share, in the three months ended Dec. 1, more than double its profit of $175.2 million, or 31 cents a share, for the same period a year earlier.
The result beat analyst expectations and the company's October forecast, sending its share price up 11.2 percent to $119.03 in after-hours electronic trade. The shares closed at $106.99 on Nasdaq.
The company said it added about 1.65 million BlackBerry accounts in the quarter -- in line with its forecast -- which brought it to a total of about 12 million. It also shipped more than 3.9 million devices.
Third-quarter revenue was $1.67 billion, up from $835.1 million a year earlier.
With December's holiday shopping season under way, RIM is in a crucial month for retail sales, which are becoming an increasingly important slice of its revenue pie.
The Waterloo, Ontario-based company has launched a number of multimedia-heavy BlackBerry models such as the Pearl to attract users other than the executives, lawyers, politicians or other professionals who still make up the bulk of its customers.
Jim Balsillie, RIM's co-chief executive, told analysts during a conference call that those efforts -- bolstered by promotions from carriers -- are bearing fruit.
He said Black Friday, the retailing day that marks the beginning of the U.S. holiday shopping season, was RIM's "strongest day ever" in terms of net subscriber additions. He added that weekend additions have been strong since then.
"This is in contrast to prior years, when we have traditionally seen a slowdown on Black Friday and the weekends following."
Carriers that offer BlackBerry smartphones have been promoting the devices and offering cheaper data plans, which has also helped stoke RIM's growth.
For the upcoming fourth quarter, RIM expects to add about 1.82 million subscribers, short of the 1.88 million that analysts were expecting.
Some observers have recently questioned whether RIM will be able to maintain its torrid pace of growth while a credit and liquidity crisis roils the financial-services companies that buy its smartphones.
But Balsillie said demand from large corporations remains robust.
"We believe that the enterprise market remains underpenetrated and that there are many opportunities for growth both in North America and markets around the world," he told analysts.
Fourth-quarter revenue should be between $1.8 billion and $1.87 billion, RIM said, with earnings between 66 and 70 cents per share -- better than analyst forecasts, according to Reuters Estimates.
"I think overall, the market is going to look at it and say they are pleased, at best, on the subscriber addition side of it. But I think it's the bottom line that the people are going to focus on," Research Capital analyst Nick Agostino said shortly after the results were released.
On the Toronto Stock Exchange, the company's shares finished C$4.43 higher at C$106.52. ($1=$1.00 Canadian) (Editing by Peter Galloway)