Small-cap stocks traded higher for most of the day before taking a hard fall along with the major indices, and

Virgin Mobile USA

( VM) was among the winners after its

initial public offering.

The prepaid-wireless outfit priced 27.5 million shares at $15 a pop, mostly from the company itself, for trade on the

New York Stock Exchange

. Underwriters have a 30-day option for about another 4.1 million shares to cover overallotments. Shares of the Warren, N.J., company were recently up 3.7% to $15.55.

Newpark Resources

(NR) - Get Report

, Texas-based purveyor of services to the oil and gas industry, jumped 10.6% to $6.26 after agreeing to sell its U.S. Environmental Services business for $81.5 million in cash to Trinity TLM Acquisitions. The deal, which will probably close by year-end, also includes a five-year earn-out provision potentially worth up to $8 million.

Agfeed Industries

( FEED), a China-based animal-feed company, leapt 7.2% to $12.85 after

Nasdaq

approved it for listing on its Global Market index. The change will effect at open of business on Friday.

Among the losers, however, was

TheStreet Recommends

Ruby Tuesday

(RT)

. Shares of the restaurant chain sank 14.4% after it pocketed just $11.1 million, or 21 cents a share, in the fiscal first quarter. That's nearly half of year-ago earnings, and it comes in a penny shy of Thomson Financial's per-share analyst expectations.

The Maryville, Tenn.-based outfit also said same-restaurant sales at company-owned locations dropped 4.8%, while domestic franchises saw a 2.9% fall. Total revenue was up 2.4% to $346.8 million. Shares surrendered $2.70 to $16.10.

In more disappointing earnings,

EZ-E-EM

(EZEM)

took a fall after income from continuing operations dropped sharply year over year to 6 cents a share, or 9 cents under the sole analyst's target. A year ago the Lake Success, N.Y., purveyor of medical devices and contrast products made 14 cents a share. EZ stock was down 19% to $15.95.

Wireless-services seller

InPhonic

( INPC) suffered one of the biggest price slides overall on word third-quarter results will be "significantly below" prior company guidance. The Washington-based company has hired Lazard to help conduct a review of financing and strategic alternatives, which among other things could include a merger, sale, strategic alliance or credit-agreement refinancing.

InPhonic has additionally ousted chief operating officer Brian Curran. Shares plummeted 61.9%, or $1.20, to 74 cents.

WJ Communications

( WJCI), based in San Jose, Calif., tumbled 26% after saying third-quarter revenue will likely range between $9.7 million and $9.9 million to fall short of the $11.6 million average Street estimate, and that fourth-quarter demand is expected to be "lower than previously expected."

The radio-frequency semiconductor firm also announced it retained Thomas Weisel Partners in order to evaluate strategic alternatives. Shares were changing hands at 89 cents.

More broadly, the Russell 2000 and the S&P SmallCap 600 were recently plunging 1.2% and 1%, respectively.