McCormick & Schmick's ( MSSR) was among the biggest small-cap losers Tuesday in a mostly down day for the sector.

Shares plunged 23.1% after the Portland, Ore., seafood-restaurant chain sliced 5 cents off the low end of its prior third-quarter income guidance to about 16 cents a share. Same-store sales are now pegged to be flat vs. the prior forecast for a gain of between 1.5% and 2.5%, and the total-sales estimate was lowered by $2 million from the earlier low end to roughly $88 million.

Thomson Financial's estimates call for 22 cents a share, less extraordinary items, on total revenue of $90.6 million. McCormick shares lost $5.78 to $19.28.

Another small-cap name, Panacos Pharmaceuticals ( PANC), slid 21% on news chief financial officer Peyton Marshall had resigned. VP Robert Pelletier will replace him in the interim. Shares of the Watertown, Mass., biotech company were off 53 cents at $1.99.

And Standard Pacific ( SPF) sank 10.6% after UBS began coverage on the Irvine, Calif., homebuilder with a sell rating. The move comes a day after the company priced a $100 million convertible-senior-bond offering and eliminated its 4-cent quarterly dividend.

Standard Pacific shares shed 75 cents to $6.30. That helped pressure the Russell 2000, which also harbors McCormick, as well as the S&P SmallCap 600. Both trackers were lately losing around 0.4%.

Strongly on the upside, however, was HandHeld Entertainment ( ZVUE). Shares catapulted 23.4% after the San Francisco-based outfit said it has filled an "initial" order for 10,000 of its Zvue 250 MP3 video players -- the largest in its history, according to the company. The products will become part of a rewards program for a "major" U.S. credit-card company, said HandHeld. Shares were trading at $2.95.

Similarly, California's Centillium Communications ( CTLM) soared 15.8% to $1.76 after scoring a multimillion-dollar order for one of its Mustang system-on-chip processor from a "leading" Japanese networking-equipment maker. The products are slated for delivery within the next six months and will ultimately "power the high-bandwidth broadband access and next-generation network services in optical fiber-to-the-premises networks for hundreds of thousands of subscriber lines," said Centillium.

Oppenheimer stamped a buy rating on AspenBio Pharma ( APPY), saying that its proposed appendicitis diagnostic-test product is promising, seems to be unique and makes the biotech company an attractive takeout candidate. Shares of the Colorado-based company leapt $1.08, or 15.7%, to $7.95.

Elsewhere in the green, Akeena Solar ( AKNS) jumped on word Suntech Power ( STP) had signed a letter of intent to make 10 to 14 megawatts worth of Akeena's Andalay solar panels in 2008. Shares of California-based Akeena ramped up 11.5% to $8.14. Suntech recently lost 1.5%.

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