VoIP service provider Jajah is offering its subscribers toll-free call buttons that they can place on their Web sites, enabling site visitors to immediately set up phone calls to Jajah subscribers in 122 countries.

In contrast to other "call me now" services, calls via Jajah can be completely free for both parties if the Web site owner and visitor are Jajah subscribers and live in the right countries, according to Jajah's Web site.

The buttons could be used by companies wanting to provide a free contact point for customers service. Other likely uses of the buttons are on social networking sites, blogs, and e-mails, said Trevor Healy, CEO of Jajah.

The subscriber can filter unwanted calls and control the cost of the call, without revealing his telephone number to the caller, Healy said.

Unlike VOIP providers offering PC-to-PC calling, Jajah, of Mountain View, Calif., offers a VoIP phone service that originates and terminates calls on standard mobile and PSTN phones.

Users are not required to download software, nor do they have to buy additional hardware to use the service. "This allows people who do not own computers to go to any Internet cafe and make a call," Healy said. They get cheaper rates if they register with Jajah for the service, however.

For the toll-free calling button, subscribers have to go to the Jajah Web site, register for the toll-free service, and tweak parameters such as the time during which they want to receive the calls, and the countries from where they would want to receive calls, according to Healy. The site will generate HTML code, which is to be included in the subscribers' blogs or Web sites.

To extend its services to people who may not be able to afford a PC or an Internet connection with which to set up the service and initiate calls, Jajah is working on a number of new technologies, including one that will allow people to access the Jajah service through a standard phone without an Internet connection, according to Healy. Another technology under development is the use of SMS on a mobile phone to initiate a call on the Jajah service.

But Jajah's promise to make calls on its service free has been delayed. The company's co-founder Roman Scharf said in July that the company would introduce in October a business model that would make businesses pay for free calls available to users. Jajah is still working on offering a free service paid for by advertising, but does not as yet have a date for its formal launch, Healy said. Already the cost of calling using Jajah is low enough not to be a deterrent to callers, he added.