Following complaints of unfair competitive practices, BT's mobile phone subsidiary, BT Cellnet, has moved to assure customers that its prepaid mobile phones do not restrict access to the Internet, the company said today.

The company had been accused by rivals of locking its prepaid handsets so customers could not access WAP (Wireless Application Protocol) portals offered by its competitors.

WAP portals are seen as a key service for directing users to shopping and information Web sites online, where customers can purchase items such as theater tickets or make reservations for restaurants.

But BT Cellnet says its prepaid handsets can be unlocked by entering a four-digit code available from the company's customer services department.

"That code has always been available, and users just need to call BT Cellnet and get the procedure for enabling the prepay phones to work that way," said Dave Massey, a BT Cellnet spokesman. None of the company's other WAP models require a code to unlock access to other portals.

WAP service provider Fonedata made an official complaint to the U.K. telecommunications regulatory authority the Office of Telecommunications (Oftel) last week, claiming that BT had programmed the telephones so as to prevent customers from accessing competing portals.

"I purchased a BT Cellnet prepaid phone myself about five weeks ago to just check out the competition and see if I could access our WAP portal," said Simon Luttrell, Fonedata's managing director. "I was unable to do it. BT says you can, but for an average, nontechnical user, it was very difficult to change the settings. That's why we made the complaint to Oftel," Luttrell said.

BT Cellnet said it had always made the code available to consumers and implied that the Mitsubishi Trium/Geo handsets BT had ordered from makers Mitsubishi came with the blocking code.

On Wednesday, Mitsubishi Electric issued its own statement firmly denying it reprogrammed the handsets and asserting that the company had set the specifications on the phones in accordance with BT Cellnet's requests.