Updated from 5:45 p.m. EDT

Trading was active after the regular markets closed, and investors used the late session to drive down shares of technology companies.

In the first 45 minutes of the extra session, 5.2 million shares changed hands on Instinet, and 3.2 million shares traded among the top 20 movers.

Sun Microsystems

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(SUNW) - Get Report

was off 3.5% to $12.96 on Instinet and was down 3.4% on Island ECN, after falling just under 1% during the regular session. After the bell, Sun said demand remained soft, and the Unix systems maker said it probably wouldn't turn an operating profit in the fiscal first quarter. Earlier in the day, Merrill Lynch cut its first- and second-quarter estimates on Sun. Goldman Sachs cut Sun's estimates on Tuesday.

Corning

(GLW) - Get Report

was one of the top losers after hours, falling 4.1% to $14. The company, which traded on light volume, set plans to cut 1,000 jobs from its fiber unit. Corning is also planning short-term shutdowns of two North Carolina facilities. Additionally, the company said it expects overall market growth for optical fiber in 2001 to be significantly less than the previous 15% growth forecast.

But it wasn't all bad news for tech companies.

Loudcloud

(LDCL)

was surging, up 36.4% to $3 after the Internet infrastructure services company said it beat analysts' expectations for the second quarter. The company also said it expects a loss of 68 cents to 70 cents in the third quarter, narrower than the loss Wall Street projected.

Ciena

(CIEN) - Get Report

, which was added to the S&P 500 after the close of trading Wednesday, fell 0.6% to $18.43 on Instinet and lost 0.4% on Island. Ciena, number one in volume on Instinet and second on Island in the extended session, gained 1.5% in regular trading.

Tech Data

(TECD) - Get Report

was up 13.9% to $37.99 on Island after topping analysts' earnings estimates. The company also raised its guidance for the third quarter.

Altera

(ALTR) - Get Report

was among the top volume movers, but remained unchanged at $28.05, after reiterating the forecast that revenue would fall 15% to 20% in the third quarter.

Cisco

(CSCO) - Get Report

was off 0.2%,

Oracle

(ORCL) - Get Report

was down 0.7% and

Microsoft

(MSFT) - Get Report

fell 0.1%.

Intel

(INTC) - Get Report

and

Dell

(DELL) - Get Report

were unchanged, while

JDS Uniphase

(JDSU)

was up 0.1%.

Exodus Communications

(EXDS)

was off 2.1% on Island.

Island ECN offers trading, mainly in Nasdaq-listed stocks, from 7 a.m. to 8 p.m. EST.

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