Stocks were mixed in after-hours trading Monday, and among the bigger winners was management-services firm

ICF International

(ICFI) - Get Report

.

The Fairfax, Va., company careened past Wall Street estimates with first-quarter income of $8.7 million, or 60 cents a share, on revenue of $151.7 million. Analysts polled by Thomson Financial were looking for 46 cents a share on $131.4 million in revenue. Shares were leaping 9.2%, or $2.19, to $25.91.

Agilent Technologies'

(A) - Get Report

rising profits

were just shy of targets for the second fiscal quarter, but next-quarter adjusted income should range between 46 cents and 50 cents a share. This is at or above consensus. Shares lifted 3.7% to $37.23.

Meanwhile, trucking company

Heartland Express

(HTLD) - Get Report

, based in Coralville, Iowa, gained 5% to $17.71 on word it declared a special $2-a-share dividend to be paid along with its 2-cent per-share quarterly distribution.

Californian biotech

CV Therapeutics

( CVTX) rose 3.8% to $10.08 after submitting for regulatory approval its Regadenoson compound -- proposed for use in the detection of coronary artery disease. This triggers a $7 million milestone payment from

Astellas Pharma

(ALPMF)

, which will handle U.S. commercialization if the compound is approved.

Among those on the postclose downswing, however, was flash-memory-devices maker

STEC

(STEC)

. The Santa Ana, Calif., company missed Wall Street's first-quarter profit estimates and guided well below top- and bottom-line expectations for the second quarter. Shares lately tumbled 13.2% to $7.06.