Updated from 12:04 p.m. EST

Shares of

Comstock Homebuilding

(CHCI) - Get Report

were among the

Nasdaq's

losers Monday, falling 9% after the homebuilder warned that fourth-quarter earnings would be below Wall Street forecasts.

Comstock sees fourth-quarter earnings of $1.01 to $1.10 a share. Analysts polled by Thomson First Call expected earnings of $1.21 a share. Comstock now sees full-year earnings of $2.50 to $2.60 a share, below its previous forecast of $2.68 to $2.73 a share. Analysts expected earnings of $2.70 a share.

Comstock also announced a repurchase plan for one million shares, and said it has begun planning an expansion into certain markets outside of its core Washington, D.C., market. Shares recently traded down $1.40 to $14.22.

J. Jill

(JILL) - Get Report

shares rose 4% after the women's clothing retailer said it has hired financial adviser Peter J. Solomon Co. to help explore strategic options, including a possible sale. The move comes after

Liz Claiborne

( LIZ) offered to buy the company last month for $18 a share. J. Jill said at the time it would review the bid. In a statement Monday, Liz Claiborne said it is pleased J. Jill has decided to review strategic alternatives, and it looks forward to participating in the process. J. Jill shares recently changed hands at $19.14, up 76 cents.

Shares of

Lions Gate Entertainment

(LGF)

slumped 11% after the movie producer and distributor lowered its fiscal 2006 earnings guidance. The company cut its earnings forecast to $15 million from its previous projection of $35 million. Lions Gate continues to expect free cash flow of more than $100 million and sales of more than $850 million. "The disappointing performance of the theatrical release

In the Mix

, coupled with recent softness of family home entertainment product, direct-to-video releases and decreasing library margins due to catalog product mix, has put pressure on this year's EBITDA," the company said. Analysts project earnings of 26 cents a share and sales of $873.2 million for the year ending March 31. Lions Gate shares recently fell $1.04 to $8.24.

General Maritime

(GMR)

fell 3% after the company rejected

Frontline's

(FRO) - Get Report

most recent takeover offer. General Maritime, an operator of crude oil tanker ships, said the $39-a-share cash offer "does not reflect the underlying value of the company and is not in the best interests of our shareholders." The company added that its "recent success in strengthening its fleet, operations and balance sheet has positioned the company to continue to achieve strong results and generate significant value and returns for its shareholders." General Maritime shares were down $1.28 to $39.20, while Frontline shares shed 85 cents, or 2%, to $42.40.

Monsanto

(MON)

rose 4% after the agricultural products company boosted its first-quarter earnings estimate. The company expects to report earnings of 20 cents a share, up from its previous view of 10 cents a share. Analysts predict earnings of 11 cents a share for the recently ended quarter. Monsanto now expects that fiscal 2006 earnings will be at the upper end of its previous forecast of $2.35 to $2.50 a share. Analysts expect earnings of $2.52 a share for the fiscal year.

"While our first quarter historically has been a smaller part of our overall fiscal year, we believe we are off to a good start," the company said. "Early indications from our seeds and traits business suggest continued growth in the upcoming season, and this growth will be a key contributor to our leadership position in the years ahead." The company continues to expect full-year free cash flow of $825 million to $900 million. Shares were trading up $3.16 to $78.51.

Shares of

Copart

(CPRT) - Get Report

fell 5% after the company posted first-quarter results that fell below expectations. The salvage vehicle company earned $22.8 million, or 25 cents a share, on sales of $119 million. Analysts expected earnings of 27 cents a share and sales of $128.6 million. A year earlier, the company earned $22.7 million, or 24 cents a share, on sales of $104.1 million. Copart said results were hurt by costs related to hurricanes Katrina and Rita. During the quarter, the company received no revenue from the sale of vehicles assigned to it as a result of the hurricanes. Copart expects to realize sales related to the vehicles in succeeding quarters, it said. Shares were trading down $1.39 to $24.12.

NYSE

volume leaders included

Boston Scientific

(BSX) - Get Report

, down 28 cents to $27.05;

Guidant

( GDT), up $5.46 to $67.28;

Johnson & Johnson

(JNJ) - Get Report

, up 7 cents to $61.28;

AT&T

(T) - Get Report

, unchanged at $25.07;

Lucent Technologies

( LU), down 3 cents to $2.80;

Liberty Media

(L) - Get Report

, down 5 cents to $7.75;

Pfizer

(PFE) - Get Report

, unchanged at $21.30;

Texas Instruments

(TXN) - Get Report

, down 68 cents to $33.43;

Chesapeake Energy

(CHK) - Get Report

, up 73 cents to $31.25; and

General Electric

(GE) - Get Report

, up 8 cents to $35.58.

Nasdaq volume leaders included

Sun Microsystems

(SUNW) - Get Report

, up 7 cents to $4.02;

Intel

(INTC) - Get Report

, down 46 cents to $26.97;

JDSU

(JDSU)

, down 8 cents to $2.61;

Cisco Systems

(CSCO) - Get Report

, down 1 cent to $17.63;

Sirius Satellite

(SIRI) - Get Report

, up 1 cent to $7.13;

Oracle

(ORCL) - Get Report

, down 23 cents to $12.53; and

Microsoft

(MSFT) - Get Report

, down 28 cents to $27.73.