Vonage's Web site was temporarily down, and some customers reported being unable to dial out using the company's Voice over IP (VoIP) service today.
"The Web site was down due to a firewall issue, which was addressed immediately," Mitchell Slepian, a Vonage spokesman, said. "In the process of repairing it, there may have been isolated minor disruptions, such as a fast busy."
Slepian did not say how many customers were affected or for how long, but said the problem has been resolved, and the site and service are working properly. He refuted some media reports that the incident was a "major outage."
In the Vonage VoIP Forum, a community site that's not run by the company, users began posting complaints and questions around 1 p.m.
Some reported hearing dial tones but not being able to place calls. Some also said they were unable to reach the company's Web site, where they hoped to find information.
While some posters shrugged off the outage, others were not so understanding.
"I use my line for business," one forum user wrote. "People are trying to get a hold of me, and I am stuck on call forwarding with no way of turning it off."
Vonage, which has more than 600,000 subscribers, is looking to increase the number of business customers and is beta testing a new service with about 75 small and medium businesses.