MONTREAL -

Research in Motion Ltd. (TSX:RIM) reported a sharp increase in quarterly profits on Thursday, beating analyst estimates for its latest quarter and forecasting better than expected growth.

The maker of the BlackBerry smartphone, which keeps its books in U.S. dollars, said it earned US$628.4 million or $1.10 per diluted share for the quarter ended Nov. 30.

That compared with a profit of $396.3 million or 69 cents per diluted share a year ago.

Revenue in what was the company's third quarter totalled $.392 billion, up from $2.78 billion in the same quarter last year.

According to Thomson Reuters the average analyst estimate had been for earnings of $1.04 per share and $3.78 billion in revenue.

The company said it added about 4.4 million net new BlackBerry subscribers in the quarter to bring its total user base to approximately 36 million.

"We are pleased to report record shipments of more than 10 million BlackBerry smartphones during the third quarter with higher than expected revenue, earnings and subscriber growth," co-chief executive Jim Balsillie said in a statement.

"RIM is experiencing a great start to the holiday buying season and the strong Q3 results and Q4 outlook clearly reflect the strength of our diversified product portfolio as well as the success of our efforts to expand into broader customer segments and new geographies while maintaining our strong position in North America."

In its guidance for the its fourth quarter, the company said it expected revenue between $4.2 billion and $4.4 billion and earnings between $1.23 and $1.31 per diluted share.

Net subscriber account additions in the fourth quarter ended Feb. 27 are expected to be in the range of 4.4 million to 4.7 million.

The average analyst estimate for the fourth quarter had been for earnings of $1.12 per share on $4.1 billion in revenue, according to Thomson Reuters.

Shares in RIM, which reported its results after the close of markets, were down 59 cents at C$67.80 on the Toronto Stock Exchange.