The long-awaited move to the use of mobile phones from different service providers on a single network got a boost Thursday with the announcement from MetroPCS Communications that it will permit customers from Verizon Wireless, Sprint, and Alltel to use MetroPCS' network.

The company said the service, called MetroFlash, will be available to customers who bring their phones to its dealers for reprogramming. The company, which offers unlimited, flat-rate wireless service, said for a $40 a-month fee, customers will receive unlimited local and long distance calling along with voice mail features and text messaging. The company said customers also will be asked to pay a $30 fee, presumably to turn on their service.

The announcement represents the first major break in providing open service for CDMA users; subscribers who have GSM service -- primarily AT&T and T-Mobile -- can use each other's service as well as service from other international GSM providers once their phones are unlocked. GSM users simply swap SIM cards from different service providers. Users with CDMA phones will have to have them programmed for MetroFlash usage.

Not since number portability have consumers been offered such a convenient option in switching service providers, said Tom Keys, chief operating officer of MetroPCS.

The company has some 4.4 million subscribers nationwide. While most cell phone service providers have hailed the coming of so-called open networks in which handsets from competing services can be universally used, the actual implementation has been virtually nonexistent to date. Most providers still lock in subscribers in two-year contracts when they get a new phone and a new service.

With MetroFlash, users will be able to use the phones they typically obtained when they signed up for, say, Verizon Wireless or Sprint.