Internet media company Yahoo Inc. (YHOO) Wednesday posted a second-quarter profit that more than doubled, but shares tumbled almost 13 percent on a weak sales outlook.

Shares in Yahoo, which had run up since April when the company surprised Wall Street with unexpectedly strong earnings, immediately fell in after-hours trade after the results only met expectations.

"After crushing numbers in Q1 and Q4 last year, everyone was expecting that Q2 was going to be stellar.... They didn't blow anything away," said Janco Partners (search) analyst Martin Pyykkonen, who added that Yahoo's third-quarter guidance was also weaker than some analysts were expecting.

Sunnyvale, Calif.-based Yahoo had a second-quarter net profit of $112.5 million, or 8 cents a share, boosted by strong advertising sales. Its year-ago profit was $50.8 million, or 4 cents a share.

Yahoo's revenue, excluding money it pays to traffic partners, grew to $609.1 million, lighter than some analysts expected. Revenue was $321.4 million a year ago.

Analysts had forecast the company to earn 7 cents to 10 cents a share on revenue of $590.6 million to $627.5 million, according to Reuters Estimates (search).

"It seems in line with the guidance, obviously, a little bit lower than expectations," said Piper Jaffray (search) analyst Safa Rashtchy. "I think that investors will take it as somewhat disappointing."

Yahoo forecast revenue, excluding traffic acquisition costs, of $610 million to $650 million for the third quarter. It raised its 2004 revenue outlook to a range of $2.46 billion to $2.54 billion.

Analysts, on average, had seen third-quarter revenue of $647.9 million and full-year revenue of $2.53 billion, according to Reuters Estimates.