JNI Corp.


was down 12.3% in preopen


trading after a

postclose warning Wednesday that first-quarter earnings will be between 3 cents and 4 cents a share, well below analysts' expectations of 13 cents and below the year-ago period earnings of 8 cents. The company, a supplier of

Sun Microsystems

(SUNW) - Get Report

, attributed the loss largely to weakness in the Sun server marketplace. Sun was down 1%.