Research in Motion (Rim) sales rose by 66 per cent in the fourth quarter to $930.4m (£470.7m), only slightly below analyst predictions of $936m (£473.5m), thanks to strong BlackBerry Pearl smartphone sales.

The mobile communications provider added one million new customers, taking its BlackBerry subscriber base to eight million.

Total annual sales rose by 47 per cent to $3bn (£1.5bn), with about 6.4 million devices shipped throughout the year. Handheld devices accounted for 73 per cent of sales, services 19 per cent and software five per cent.

‘We are extremely pleased with record sales of $3bn,’ said Rim chief executive Jim Balsillie.

‘We are entering the next financial year with very healthy subscriber growth momentum, a strong slate of products, exceptional partnerships and a growing market leadership position.’

The strong results came despite increasing competition from Palm’s Treo, Motorola’s Q, Samsung’s Blackjack and market leader Nokia’s smartphones .

The firm is also subject to higher costs because of a formal investigation by the US Securities and Exchange Commission over its practices regarding internal stock option grants.

But Balsillie is bullish, predicting continuing growth and first-quarter sales of $1bn (£500m).

Low prices and improved connectivity are behind the strength of the mobile PDA market, says Butler Group analyst Sarah Burnett. ‘Rim is facing stiff competition, but has launched new products and functionality to keep its leading position,’ she said.