OSLO, NORWAY: Norwegian browser maker Opera Software swung to a surprise third-quarter loss, hit by a strengthening Norwegian crown and costs from tailoring products, sending its shares down to an eleven-month low.

Opera - the world's largest mobile browser maker - posted a third-quarter pretax loss of 16 million crowns ($2.8 million), against expectations for a 17 million profit in a Reuters poll.

Sales rose only slightly from a year ago to 135 million crowns, well below all analysts estimates, which ranged from 153 million to 168 million.

"This was significantly weaker than what we had expected, and it does not look to improve until second half of 2010," analyst Fredrik Thoresen at DNB NOR says.

Shares in Opera fell 25.4 percent to 17.30 crowns by 1224 GMT.

Opera said it would, at best, reach breakeven in the fourth quarter, with revenues of 140-145 million crowns and expenses at 145-150 million crowns.

"We reached the bottom during the third quarter, and I have no doubt that it will again move upwards," Chief Executive Jon S. von Tetzchner told Reuters on the sidelines of a news conference.

"Of course it is not much fun to deliver such weak results when we are used to deliver 40-50 percent yearly growth."