For many cell-phone users in Costa Rica, there's good news: your phone just got a passport.

The Costa Rican Electricity Institute (ICE) has announced that international roaming is now available for all of its 900,000 Ericsson cell phone lines.

This adds to 400,000 users who have cell lines provided to ICE by Alcatel, which already had international roaming.

To activate the service, users must be current on their bills and show up at any ICE telecommunications office. Along with standard documentation, subscribers must also pony up a minimum $150 deposit.

According to ICE, the deposit is a guarantee that users won't run up a large tab while abroad and then not pay itp. If a user's bill reaches $150, the service will be suspended, ICE added. That limit can be raised by leaving a larger deposit, however.

Charges per minute and per text message will depend on the local network. Roaming will be available only in countries where ICE has a contract with local networks.

With this service upgrade, international roaming is now available to all subscribers with GSM lines, one of Costa Rica's two cellular systems.

TDMA, the other system, uses an older technology, has 850 MHz frequencies and is in the hands of about 425,000 users. GSM phones, a newer, yet less reliable system, have 1,800 MHz frequencies and are used by 1.26 million users nationwide, according to ICE.