Cingular Wireless said it is selling its messaging technology unit to institutional investor Cerebrus Capital Management for an undisclosed sum. The deal includes network and IT systems, customer service operations and a majority of subscribers.

The Cingular Interactive subsidiary provides wireless corporate e-mail and messaging through its Mobitex packet data service. The Mobitex network supports approximately 25 percent of all Blackberry users worldwide, the company said.

The unit also sells applications enabling field force automation, telemetry and remote transaction processing. Cingular will continue to offer the Mobitex service under a deal with the Cingular Interactive unit.

"The Mobitex resale agreement with Cingular Interactive, combined with our GPRS/EDGE (define) (define) networks, gives Cingular customers the maximum flexibility in finding wireless data products to suit their needs," Cingular COO Ralph de la Vega said in a statement.

Cingular Interactive is based in Woodbridge, N.J. and its managers are expected to remain following the sale.

Cingular Wireless is a joint venture between Baby Bells SBC Communications (Quote, Chart) and BellSouth (Quote, Chart).