So imagine his surprise late last month when he left a heated policy debate to dial a number saved in his phone's memory and a recorded woman's voice answered. The recording told him, "press 1 if you want to meet a friend, press 2 if ..."

Mr. Ogawa, whose phone has been bombarded with hundreds of unwanted e-mail messages as well, knew he had come ear to ear with the newest mobile come-on: the one-giri spam scam.

One-giri is Japanese shorthand for computers that dial numbers randomly, ring once and hang up. The callers - usually dating services that phone thousands of numbers randomly - are not charged because no one picks up.

But the incoming call leaves a phone number on the receiver's handset. Curious to see who called, unsuspecting Japanese redial and get an offer they generally rush to refuse, lest they run up extra charges.

The simple scheme is the latest in a battle to reach consumers' pockets via their cell phones. Japan is a natural breeding ground for the pesky, but largely legal, pitches: The country has 60 million mobile phones in use, consumers are often trusting, and privacy laws are lax. But the sleazy nature of the pitches and their rapid proliferation are turning a hit product into a headache.

While cellular service providers like NTT DoCoMo Inc. and Japan Telecom Co.'s J-Phone benefit from the increased data traffic sent on their networks, customer complaints are soaring. In addition to suffering bad public relations, the carriers are seeing their network computers overload, slowing transmission times and forcing the carriers to mobilize an army of software programmers.

NTT DoCoMo, which runs the market leading i-mode service, processes 950 million cell-phone data messages a day, yet a staggering 85 percent of them are sent to nonexistent addresses, most by computers that randomly generate numbers and send messages searching for active accounts.

The company says one-fifth of the 30,000 complaints it received in October were about annoying e-mails.

Cell-phone providers are striking back. DoCoMo will spend ¥1.1 billion ($8.7 million) this year to block unwanted bulk mail from entering its servers. The company also lets customers limit incoming e-mail to 10 domain addresses of their choice and gives users a monthly credit for 400 free packets, the bundles of data that are sent as messages.

On the legal front, DoCoMo has won a temporary injunction against a company in Yokohama that sent spam mail to huge numbers of invalid addresses. Mr. Ogawa, the lawmaker, even submitted a bill to Parliament seeking to penalize people sending bulk e-mail, though he expects the government to reject it because of the difficulty in policing spammers.

Programmers continue to develop algorithms sophisticated enough to bypass server walls and create lists of valid addresses that can be resold.

Optomail Inc., a Tokyo-based company that manages online marketing campaigns, has received a dozen unsolicited requests to send bulk e-mail. The company requires proof that the addresses were acquired with the users' consent, which deters most would-be clients.

"We make clear we are not a list broker, and when we see a bunch of mobile addresses on the list, it's a big red flag," said Richard Chen, Optomail's chief executive officer.

The digital epidemic may spread beyond Japan's shores. DoCoMo is preparing to introduce its i-mode network in Europe via partnerships with KPN Mobile NV of the Netherlands and others.

For all its convenience and new features, though, the service could flop if DoCoMo fails to build firewalls to protect privacy-conscious customers.

In a recent vote, the European Parliament declined to address the issue of spam on next-generation phones.

"Cell phone spamming is going to turn off European consumers right away," said Jamie Cattell, a director in Tokyo for Research International, a British company that conducts consumer research online globally.

In the meantime, Japanese cell-phone providers are urging users to change their addresses frequently and to refuse to return calls from unknown numbers.

Mr. Ogawa has tried all that and still gets spammed.

"It's an endless game of cat and mouse," he said.

The full article was at International Herald Tribune