All told, Frontier's long-distance revenue will be $400 million in the fourth quarter, a 20 percent decline from the previous quarter.

Only 5 percent of Mobilcom's long-distance revenues come from registered subscribers.

A comparison of the Baby Bells' long-distance revenue with their costs reveals the problem.

Among other things, Sprint said its long-distance revenues would grow less than 10 percent in the fourth quarter, compared with a year earlier.

During the last year, the long-distance revenues of the company increased by only about 1.5 percent, compared with the industry average of nearly 5 percent.

"Phone companies feel this would diminish their long-distance revenues," he said.

Although traditional long-distance revenues grew consistently between 1984 and 1997, they're now in a period of steady decline".

AT&T's long-distance revenues rose only 2.2 percent in the third quarter of 1996, compared with 7 percent for the entire industry.

A.T.&T. rose 41.2 percent, to $596 million, on the strength of long-distance revenues.

Of course, tension between Internet service providers and phone companies concerned about a loss of long-distance revenue is hardly new.