NEW YORK ( TheStreet) -- Several stocks trading near $5 were poised to move on above-average volume during Thursday's session.

On2 Technologies ( ONT) surged by 15 cents, or 26.1%, to 74 cents in the premarket session after Google ( GOOG) revised terms of its merger agreement with the company. Each shareholder On2 common stock will receive 0.0010 of a share of Google Class A Common Stock for each share, as previously announced by On2 and Google, plus an additional 15 cents per share in cash consideration. More than 3.3 million shares changed hands in the premarket session compared to the three-month daily average volume of 942,000, according to Yahoo! Finance.

GenVec ( GNVC) rallied by 13 cents, or 9%, to $1.57 in the premarket session after Roth Capital initiated coverage of the stock with a buy rating and a $4 stock price target, citing GenVec's lead product, TNFerade, which is currently in a pivotal Phase III study for the treatment of pancreatic cancer. The 50-day average daily volume for GenVec is 1.61 million shares, according to the Nasdaq.

Pier 1 Imports ( PIR) jumped by 37 cents, or 6.8%, to $5.85 in the premarket session after the company said same-store sales rose 8.6% in December, compared to a year-ago decline of 10.2%. The retailer also said that for the five weeks ended Jan. 2, sales rose 5.6% to $207 million. The three-month average daily volume for Pier 1 is 2.52 million, according to Yahoo! Finance.

HealthTronics ( HTRN) rose by 31 cents, or 12.7%, to $2.75 in the premarket session after the company upped its financial guidance following its acquisition of Endocare. HealthTronics now expects an earnings before interest, taxes, depreciation and amortization, or EBITDA, contribution in the fourth quarter of $2.75 million to $3.25 million, up from the prior range of $1 million to $1.5 million. HealthTronics also said it now expects a first-quarter annualized EBITDA contribution from the Endocare acquisition of $11 million to $13 million, well above the prior guidance range of $6 million to $7 million. The 50-day average daily volume for HealthTronics is 44,000 shares.

( Earlier at 7:27 a.m. EST.)

Pacific Ethanol ( PEIX) shares rallied more than 20% after the company said it has resumed production at its Magic Valley facility, which is now producing and selling ethanol and feed products. Production at the facility was suspended in February due to poor market conditions. The 50-day average daily volume for Pacific Ethanol is 983,000 shares, according to the Nasdaq. Late Wednesday, shares jumped 20.9% to 95 cents.

Christopher & Banks ( CBK) was set to slide Thursday after the apparel retailer reported third-quarter earnings of 19 cents a share, worse than the Thomson Reuters average estimate for a profit of 21 cents a share. Sales fell 7.7% from a year ago to $132 million, matching consensus. The company also said it expects fiscal fourth-quarter same-store sales to decline in the high single digits. The three-month average daily volume for Christopher & Banks is 211,000 shares, according to Yahoo! Finance. The stock finished Wednesday at $7.66 but fell nearly 9% to $6.98 in the late trading session.

ZymoGenetics ( ZGEN) shares dropped 10.6% in Wednesday's after-hours session and should open lower Thursday after the biotech company announced a 12 million common stock offering. The 50-day average daily volume for ZymoGenetics is 390,000 shares. Shares closed Wednesday at $6.77 but fell to $6.05 in the late trading session.

Hot Topic ( HOTT) shares were poised to slide after the teen retailer late Wednesday said same-store sales fell 10.9% in December. Hot Topic also revised its fourth-quarter earnings guidance lower, now expecting a profit of 18 cents to 20 cents a share, below its prior guidance of 23 cents to 26 cents and worse than the Thomson Reuters consensus of 24 cents a share. The 50-day average daily volume for Hot Topic is 1.35 million shares. Shares were down 5.7% to $5.62 in the after-hours session Wednesday.

Zix Corp. ( ZIXI) was set to rally Thursday after the Internet-based software company late Wednesday reaffirmed its fourth-quarter guidance for earnings of a penny to 2 cents a share, compared to analysts' expectations that it will break even in the quarter. Revenue should fall between $7.9 million and $8.1 million, Zix said, in line with the Thomson Reuters consensus target of $7.98 million. Zix also offered stronger-than-expected earnings and revenue guidance for 2010. The 50-day average daily volume for Zix is 353,000 shares. The stock closed at $1.70 Wednesday before rising 7.7% in the late trading session.

-- Written by Robert Holmes in Boston.

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