The moves by regional ISPs Shentel, in Virginia and Maryland, and CIS Internet, in West Virginia, come a few months after national ISP Earthlink began offering the service in July.
Subscribers to these services can retrieve unread e-mail and listen to their messages over a telephone or cell phone through text-to-speech technology. They can respond to messages verbally, sending a recorded audio file attachment in e-mail. The cost varies between about $5 and $8 a month.
All three ISPs use technology developed by Audiopoint, a speech applications company. The Fairfax, Va.-based company also sells voice-activated dialing technology and other speech recognition applications for businesses.
Analysts say the technology hasn't been that successful, in part because of the various symbols, typos, foreign words and other unusual characters that can appear in e-mail.
"I haven't seen a whole lot of successes because listening to e-mail has a lot of gotchas," said Alan Reiter, president of an industry consulting company called Wireless Internet & Mobile Computing. "E-mails are not written to be read, and the people sending them don't have voice mail in mind. That is a problem."
Additionally, the service eats up valuable minutes, particularly on lengthy e-mail messages.
Audiopoint said its technology allows subscribers to establish service preferences, including filtering rules that skip spam and junk mail.
Still, resistance to using cell phones for anything other than conversation is high in the United States. Fewer than two million of the nation's 140 million cell phone users access the Web on their phones, analysts say.