WASHINGTON--An estimated 4 million subscribers to Internet phone services like Vonage could see new fees on their bills under a plan approved Wednesday by federal regulators. The Federal Communications Commission voted unanimously at its monthly meeting here to require all voice over Internet Protocol services that connect to the public-switched telephone network--as opposed to using peer-to-peer technology, like Skype--to contribute to the Universal Service Fund. The $7.3 billion fund, which has been a feature of U.S. policy for more than 70 years, subsidizes telephone service in rural and low-income areas. It also runs a controversy-plagued program called E-Rate that provides...