(FORTUNE Magazine) – Even if those ubiquitous Ugg boots haven't hit your own personal fashion "don't" list, the stock of the company that makes the woolly mammoth--inspired knee-highs probably should. Since September, shares of Deckers Outdoor (DECK, $28) have soared 180% on the heels of sudden demand for its UGG boot line. Sported last year by actresses like Pamela Anderson and Sarah Jessica Parker, the sheepskin boots were prized among the fashion forward, who paid up to $185 for a pair. In the first quarter of 2004 sales climbed 23% higher than a year ago, to $44.3 million.

Both the boots and the stock, however, suffer from overexposure. Decker's now trades at 32 times its trailing earnings, which is substantially pricier than footwear foes like Reebok (P/E of 15) or Timberland (P/E of 18). Meanwhile, short-selling interest in the stock has risen to 1.5 million shares--that's 15% of its outstanding shares, or five times its daily trading volume!

Defenders of Deckers, which also makes Teva sandals, say Uggs are much more than a passing faux pas. But even company management seems uncertain the boots will march on. A secondary stock offering is in the works, which will allow executives, including CEO Doug Otto, to unload two million shares of their own stock.

--Julie Creswell