Vonage

(VG) - Get Report

, provider of broadband telephone service, swung into its first-ever profit in the quarter, sending shares soaring in afternoon trading.

During the first-quarter the company earned $5 million, or 3 cents a share, up from a loss of $9 million, or 6 cents, in the year-ago period.

The results included a $13 million mark-to-market adjustment relating to the derivative liability in the company's convertible debt. Without the adjustment, Vonage would have reported a net loss of $7.7 million.

Revenue remained flat at $224 million.

The company lost 6,000 subscribers and ended the quarter with 2,583,861 subscribers, down from the 2,610,360 it had a year ago.

Shares of the company skyrocketed 25% in afternoon trading to 60 cents.

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