Priceline.com

(PCLN)

beat analysts' expectations after the close on Monday but still managed to disappoint investors by issuing cautious guidance.

The online-travel company surpassed consensus second-quarter earnings expectations by a penny a share. But priceline predicted that its third-quarter and possibly its full-year earnings will fall short of expectations.

The company's stock sunk on the news, down $2.73, or 11.5%, to $21 in recent after-hours trading. The shares closed Monday's regular trading up 5 cents, or 0.2%, to $23.73.

In the just-completed quarter, priceline earned $11.4 million, or 29 cents a share. That was up from the year-ago period, when the company earned $7.7 million, or 20 cents a share.

The company's revenue rose 8.3% to $259.39 million.

On a pro forma basis, which excludes stock-based compensation expenses, charges related to its acquisition of Travelweb and other expenses, priceline would have earned $12.8 million, or 32 cents a share.

On this basis, analysts polled by Thomson First Call were expecting the company to earn 31 cents a share on revenue of $258.32 million. In June, the company

upped its guidance to a pro forma profit of 29 to 32 cents, on sales growth of 6% to 9%.

Looking forward, priceline expects to earn 21 to 26 cents a share in the third quarter, or 25 to 30 cents a share, excluding charges. In the fourth quarter, the company is projecting profit of 11 to 15 cents a share, or 13 to 17 cents per share on a pro forma basis.

On a full-year basis, the company's earnings guidance implies pro forma profits ranging from 83 to 92 cents a share.

The company expects its revenue to jump 5% on an annual basis in each of the next two quarters.

Meanwhile, Wall Street was looking for pro forma profit of 31 cents a share on $252.54 million in revenue in the third quarter. For the full year, the Street expects earnings, excluding charges, of 90 cents a share on revenue of $923.89 million.

Priceline is only the latest Internet company to let down shareholders. Last month, investors sold off

Yahoo!

(YHOO)

,

Netflix

(NFLX) - Get Report

,

eBay

(EBAY) - Get Report

,

Amazon.com

(AMZN) - Get Report

and

Blue Nile

(NILE)

after those companies either missed expectations or issued below-consensus guidance.