What many mobile users fear is coming true – spam messages to phones is becoming a real nuisance in Japan, the country that is in some ways most advanced in mobile technology.

Japanese mobile telco NTT DoCoMo ran a series of ads last week highlighting unwanted junk email, or spam, on its extremely popular I-mode service something that is attracting the critical eyes of users and government alike.

I-mode telephones come set up with an e-mail address that matches the handset's telephone number - something like [email protected] This makes them easy targets for bulk mailers who can send millions of email messages to random I-mode address for no charge.

Unless they change their address to something else, users are left to wade through a mountain of spam every time they open their email and, because of I-mode's charging structure, have to foot the bill for downloading such mail to their telephones.

All of this has DoCoMo's users, who collectively send 80 million messages and receive 100 million messages per day, complaining to the telco. European users would probably suffer the same charging mechanism.

See PC Advisor's previous stories (below) on spam text messages and phone junk mail for further background.