Adaptec (NASDAQ:ADPT) took a 7% spanking today, bringing the shares to just under $10. Yesterday's third-quarter earnings release sparked the beating, after the tech company revealed a $0.03 loss per share (identical to last year's Q3 loss) on a 5.6% increase in sales.

You don't remember Adaptec? It was better known a few years back -- before plug-and-play technology like USB and FireWire -- when Mac and PC users still had to struggle with stuff like "scuzzy" cards. These days, Adaptec's hopes are still pinned on connection technology for data storage, but with more arcane enterprise applications like iSCSI and Fiber Channel over IP -- stuff familiar only to geeks and IT professionals.

Adaptec's earnings headlines trumpet the revenue growth and a pro forma (read: sorta make-believe) earnings increase of a nickel per share, but there are unhappier numbers below the surface that help to explain the Street's jitters.

Operating cash flows were down from $14.4 million to $11.1 million. Then there are the net revenues. The $6.1 million increase, to $115 million, over last year's fiscal third quarter includes a $19.4 million influx from two recent acquisitions. That means the third-quarter revenues on Adaptec's core, pre-acquisition operations actually dropped $13.3 million (about 12%).

Shareholders are justified in worrying when the new ponies in the stable are the sole drivers of increased revenue. And there's also another purchase on the horizon, Elipsan Limited, a maker of storage virtualization software.

Over the past year, Adaptec's risen from $6 a share to over $10. That's 70 times this year's earnings estimates, and 50 times estimates for fiscal 2005. That's rich by the stock's historical standards, and it looks awfully expensive for a company that's playing so many wild cards.

Seth Jayson longs for the good old days of DOS prompts. He reads electro-mail at FoolS@sethj.com .