Viceroy Exploration ( XVE) soared on news that Yamana Gold ( AUY) had agreed to acquire the Vancouver-based mineral exploration company.

Yamana is offering 0.97 shares for each Viceroy share. The value of the transaction is C$10.86, or about $9.72 a Viceroy common share, representing a premium of 25.5%. Viceroy gained $1.78, or 23.1%, to $9.48 recently. Yamana was off 30 cents, or about 3% to $9.75.

CDC Corp. ( CHINA) gained after the Hong Kong-based online company said its China.com unit formed a strategic partnership with search engine titan Google ( GOOG - Get Report).

Under the agreement, Google will provide search engine technology for China.com to support searches of its English and traditional Chinese content by its users in greater China. Shares of CDC climbed 51 cents, or 11%, to $5.15 recently. Google was up $2.16, or 0.6%, to $389.88.

Quality Distribution ( QLTY) climbed after the Tampa-based trucking company was upgraded by Stifel Nicolaus to buy from hold. Shares gained $2.01, or 16.5%, to $14.16 recently.

Sonic Solutions ( SNIC) saw its shares rise after the company said Sony ( SNE) has chosen its Roxio digital media software for Blu-ray Disc to power data-burning capabilities for two new Vaio computers.

The software will be used with the AR notebook and RC desktop. The Roxio software will allow users to archive of up to 50 gigabytes of data. Recently, Sonic's shares were rising $1.12, or 7.5%, to $16.09.

The Buckle ( BKE) stumbled after the Kearney, Neb., retailer reported a drop in its second-quarter profits.

The company earned $6.6 million, or 33 cents a share, in the quarter. A year ago, Buckle earned $7.6 million, or 38 cents a share. Sales dropped 1.7% from a year ago to $102.4 million. Same-store sales fell 5.7%. Shares of Buckle were losing $1.81, or 5%, to $34.75 in recent trading.

Stage Stores ( SSI - Get Report) will delay the release of its second-quarter results in order to complete an internal review of its inventory-valuation methodology, and the retailer said it might have to restate its past financials.

The company said its earnings guidance for the second quarter and fiscal year should no longer be relied upon. Shares of Stage were dropping $3.75, or 11.8%, to $28.16 on volume that was about 10 times heavier than normal.

Stage, a seller of apparel, cosmetics and footwear, said it can't quantify the impact on its historical financial statements. However, it has concluded that either a retroactive application of a preferable accounting methodology or a restatement of its previously issued results could be required.