The stock was last quoted at $18.10, down 10.8%, on volume of nearly 730,000. Based on Wednesday's regular-session close at $20.29, the shares are down more than 40% in the past year. Finisar also forecast non-GAAP earnings of 18 to 22 cents a share on revenue ranging from $235 million to $250 million for its fiscal fourth quarter ending in April. That view is below the current consensus estimate for a profit of 25 cents a share in the quarter on revenue of $253.5 million. "Sales of datacom products were strong," said Jerry Rawls, the company's executive chairman, in a statement. "Gross margin was relatively unchanged from the preceding quarter, despite the impact of one month of the annual price reduction for telecom products. We held operating expenses below plan, so that operating income and operating margin increased relative to the preceding quarter." The news was impacting shares of the other main optical networkers in the extended session with Ciena ( CIEN), down 2% to $14.60 on volume of more than 90,000; and JDS Uniphase ( JDSU), losing 2.5% to $12.70 on volume of nearly 100,000. Check out TheStreet's quote page for Finisar for year-to-date share performance, analyst ratings, earnings estimates and much more.