Aether Systems

(AETH)

was down 12.5% in midafternoon after forecasting a 2001 loss of $3.90 to $3.98 a share, wider than the

First Call/Thomson Financial

estimate of $2.25.

The provider of wireless data products and services said it plans to step up investments as it pushes toward profitability. The company predicted it would turn profitable on an EBITDA basis in the third quarter of 2002, six months earlier than expected.

Aether late Tuesday posted a fourth-quarter loss of 90 cents a share, beating the Street's estimate of $1.