Jaxtr free call service jumps tenfold to 5 million

By Eric Auchard

LONDON, Dec 11 (Reuters) - Jaxtr Inc, which allows mobile phone users to bypass international call charges by using the Web, has signed up more than 5 million members and is hiring a Silicon Valley veteran to help keep pace with the growth.

Chief Executive Konstantin Guericke his company has seen membership increase tenfold in the past 140 days from 500,000, a growth surge once seen for Web phenomena like calling service Skype or instant message network ICQ.

In response, Jaxtr is hiring Taneli Otala as its vice president of engineering. He is a former technology chief at Various Inc, owner of the sex match-making site AdultFriendFinder.com that boasts 24 million members.

The Finnish database expert was previously chief technology officer at MySQL, whose database software runs many of the most heavily trafficked sites on the Web.

"We've had some system challenges keeping the servers running that make the phone calls go through," Guericke said. "(Taneli) is one of the few people who can handle our growth."

Jaxtr's service connects both fixed-line and mobile phones over the Web using e-mail addresses to identify callers. With just 20 employees, the company is one of more than a dozen start-ups seeking to build on the success of market pioneer Skype, owned by online auction leader eBay Inc (EBAY.O: Quote, Profile, Research, Stock Buzz).

But while Skype mainly lets users make free overseas phone calls via their computers, new Voice over Internet Protocol (VOIP) services allow both callers and recipients to use normal phones to converse.

Jaxtr also lets users pick up the phone and dial a local number to reach friends or family overseas, without having to return regularly to the computer to manage their account.