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What: Shares of Acme Packet (Nasdaq: APKT) got crushed today, down by as much as 18% today, after the company reported disappointing earnings, swinging to a loss.

So what: Revenue in the second quarter declined 15% to $67.6 million, and the bottom line changed from black ink to a light shade of red. Acme Packet posted a net loss of $127 million, which rounds to $0.00 per share, much worse than the $14 million in profit a year ago.

Now what: These figures were mostly expected, as Acme Packet gave a warning a couple weeks ago on what to expect this quarter. However, the new information today is that the company is also cutting full-year outlook, and now expects revenue between $270 million and $275 million, which should result in a GAAP net loss of $0.07 to $0.11 per share. On an adjusted basis, it expects earnings per share of $0.43 to $0.47, which still doesn’t compare to the Street’s forecasts.

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Fool contributor Evan Niuholds no position in any company mentioned. Click here to see his holdings and a short bio. Motley Fool newsletter services have recommended buying shares of Acme Packet. The Motley Fool has a disclosure policy. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. Try any of our Foolish newsletter services free for 30 days