Semiconductor company

Xilinx

(XLNX) - Get Report

was the most actively traded stock on Instinet and the No. 3 mover on the Island ECN after reaffirming its guidance for the fiscal second quarter.

The company still expects revenue to decline by 20% to 25% from the top line of $289 million in the fiscal first quarter. The company also said it expects to take an inventory write-down in the range of $65 million to $85 million in the quarter. The shares were off 0.1% to $36.35 on Instinet, and the stock lost 1.4% on Island.

McDonald's

(MCD) - Get Report

continued to slip in the extended session, dropping 4.4% to $27.66. The fast-food giant was off more than 3% during regular-session trading after a Salomon Smith Barney research note warned of a possible drop in sales in Japan following the first discovery of mad cow disease in the country.

Finisar

(FNSR) - Get Report

was the biggest loser on Instinet, falling 11.5% to $7.30. The company said it plans to offer $200 million of convertible subordinated notes due 2008 in a private placement. Finisar also said it may issue up to an additional $30 million of notes to cover any overallotments.

Alamosa Holdings

(APCS)

, a provider of wireless personal communication services, was giving back the gains from the regular session as it slid 2.1% to $12.95.

Active Power

(ACPW)

, which fell 7.2% in regular trading, was one of the biggest gainers on the Instinet chart, adding 2% to $5.10.

Shares of B2B software company

Ariba

(ARBA)

were up 10.1% to $2.28 on Island after jumping 10.1% during the day. After the closing bell, the company said

Home Depot

(HD) - Get Report

has selected the Ariba Buyer and Ariba Sourcing software for business uses.

Other tech names were moving in the after-hours.

Cisco

(CSCO) - Get Report

was up 0.3%, while

Applied Materials

(AMAT) - Get Report

was off 0.3%.

Oracle

(ORCL) - Get Report

gained 0.7% and

Altera

(ALTR) - Get Report

was up 0.7%.

Intel

(INTC) - Get Report

was unchanged,

Microsoft

(MSFT) - Get Report

rose 0.1%, and

Dell

(DELL) - Get Report

dropped 0.1%.

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

Confused?

TheStreet.com

explains how the rules change when the sun goes down in Investing Basics: Night Owl, a section devoted to after-hours trading.