The top after-market NASDAQ Stock Market gainers are: j2 Global Communications, Westell Technologies, Winn-Dixie Stores, Commercial Vehicle Group, and Merge Healthcare. The top after-market NASDAQ Stock Market losers are: Smith Micro Software, Liquidity Services, Cavium Networks, Black Box, and OpenTable.

Gainers

j2 Global Communications, Inc. (JCOM) stock jumped 13.47 percent to $29.48 in the after-market trading. Adjusted profit for the second quarter was $30.6 million or $0.65 per share, up from $21.0 million or $0.46 per share last year. Revenue grew 39.8 percent to $85.7 million. Analysts had expected profit of $0.58 per share on revenue of $83.9 million. Looking ahead into full year 2011, the company raised its adjusted earnings guidance to range of $2.46 to $2.56 per share from previous forecast of $2.21 to $2.42 per share. The company also increased its adjusted revenue outlook to range of $335 million to $345 million from previous range of $320 million to $340 million. Street analysts predict profit of $2.37 per share on revenue of $335.2 million for the full year.

In addition, the company's board of directors approved the initiation of first quarterly dividend of $0.20 per common share, which will be paid on September 19, to all shareholders of record as of the close of business on September 2.

Westell Technologies Inc. (WSTL) stock climbed 12.89 percent to $3.24 in the after-market trading.

Winn-Dixie Stores Inc. (WINN) stock advanced 11.30 percent to $8.96 in the after-market trading.

Commercial Vehicle Group Inc. (CVGI) stock grew 9.76 percent to $10.35 in the after-market trading.

Merge Healthcare Inc. (MRGE) stock gained 9.31 percent to $5.40 in the after-market trading. Loss for the second quarter narrowed to $3.3 million or $0.04 per share from $31 million or $0.39 per share last year. Adjusted earnings were $5 million or $0.06 per share, compared to a loss of $4.1 million or $0.05 per share last year. Revenue grew to $55.6 million from $29 million, while pro-forma revenue increased to $57 million from $41.5 million. Analysts had expected profit of $0.02 per share on revenue of $54.99 million.

Losers

Smith Micro Software Inc. (SMSI) stock plunged 16.22 percent to $2.79 in the after-market trading. Adjusted loss for the second quarter was $5.21 million or $0.15 per share, compared to a profit of $6.83 million or $0.20 per share last year. Revenue fell to $16.11 million from $31.36 million. Analysts had expected a loss of $0.11 per share on revenue of $17.81 million. For the fiscal third quarter, the company expects revenue of $15 million to $20 million, while Street predicts $23.68 million.

Liquidity Services, Inc. (LQDT) stock fell 11.11 percent to $24.435 in the after-market trading. Loss for the third quarter was $1.06 million or $0.04 per share, compared to a profit of $2.99 million or $0.11 per share last year. Adjusted earnings were $0.52 per share, up from $0.15 per share last year. Revenue grew to $86.06 million from $72.75 million. Analysts had expected profit of $0.20 per share on revenue of $82.30 million. Looking ahead into the fourth quarter, the company expects adjusted earnings of $0.18 to $0.20 per share, while Street predicts $0.17 per share. For the fiscal 2011, the company raised its adjusted earnings guidance to range of $1.10 to $1.12 per share from previous forecast of $0.73 to $0.77 per share, while Street predicts $0.77 per share.

Cavium Networks, Inc. (CAVM) stock tumbled 9.89 percent to $28.89 in the after-market trading. Profit for the second quarter was $1.9 million or $0.04 per share, up from $0.6 million or $0.01 per share last year. Adjusted earnings were $18.4 million or $0.34 per share. Revenue grew 43.7 percent to $71.6 million. Analysts had expected profit of $0.32 per share on revenue of $71.58 million.

Black Box Corp. (BBOX) stock declined 9.87 percent to $25.84 in the after-market trading. Profit for the first quarter was $9.6 million or $0.53 per share, down from $13.1 million or $0.75 per share last year. Operating earnings were $10.9 million or $0.60 per share, down from $14.7 million or $0.84 per share last year. Revenue grew 2 percent to $268.4 million. Analysts had expected profit of $0.80 per share on revenue of $261.10 million.

"In the first quarter, we saw our gross margins decrease which is attributable to our strategic pricing initiative. I am confident that obtaining these new engagements will ultimately result in a return to historic adjusted operating income levels," said Terry Blakemore, president and chief executive officer of Black Box.

For the second quarter, the company expects operating earnings of $0.81 to $0.86 per share and revenue of $278 million to $283 million, while Street predicts profit of $0.96 per share on revenue of $291.10 million. For the full year, the company anticipates operating earnings of $3.25 to $3.40 per share and revenue of $1.115 billion to $1.13 billion, while Street predicts profit of $3.55 per share on revenue of $1.11 billion.

OpenTable, Inc. (OPEN) stock decreased 9.45 percent to $62.39 in the after-market trading. Adjusted profit for the second quarter was 8.1 million or $0.33 per share, up from $3.6 million or $0.15 per share last year. Revenue grew 53 percent to $34.3 million. Analysts had expected profit of $0.27 per share on revenue of $35.31 million.

Separately, OpenTable said it has appointed Duncan Robertson as its Chief Financial Officer, effective August 23. Robertson succeeds Roberts, who was promoted to president and CEO in early June. He comes to OpenTable after co-founding and serving as CFO of mobile application software company SnapStick, Inc.