Shares of J. Crew Group Inc. (JCG) have fallen sharply in heavy after-hours trading. After the close, the retailer reported second-quarter net income of $18.1 million, or 28 cents per diluted share, down from $20.6 million, or 32 cents a share, a year earlier. The results were below the Street view of 32 cents a share.

Revenues rose 10% to $336.3 million.

The company also lowered its guidance for fiscal 2008, due to the troubling macroeconomic environment and the disruption caused by a systems upgrade.

For fiscal 2008, it now expects diluted earnings per share of $1.44 to $1.54, down from previous guidance of $1.70 to $1.75.

Using history as a guide, shares of JCG tend to fall further the next day following a drop in after-hours trading on an earnings disappointment. Late traders can take advantage of any rise to the $23.50 area,  the high end of the post annoucement price range.  The chart below shows the price activity after the close this evening. Watch out below!