The Plaxo Inc. online service automatically updates e-mail address books as contacts update their own contact information, such as e-mail and home addresses or home, work and cell phone numbers.
The new release, a plug in for Thunderbird, will allow users to synchronize their current Plaxo address book with the Thunderbird address book.
Called the Plaxo Toolbar for Thunderbird, the latest version allows the company to extend the reach of its service beyond its primary platform, Microsoft Outlook and Outlook Express.
Users can also import contacts from major Web mail accounts, including Hotmail, Netscape, Palm and Yahoo.
"It takes the hassle out of keeping track of your contact information because if you look in your address book, it is just correct all of the time," Todd Masonis, founder and vice president of product with Plaxo based in Mountain View, Calif.
"When we first started out, the biggest challenge really was about getting user adoption because obviously Plaxo would have no value unless everyone you know already used Plaxo," Masonis said.
However, since 2002, when Plaxo was first introduced, the number of users has grown to more than 5 million and demand for the service on different platforms has also increased.
Mozilla released Thunderbird in December 2004, and the foundation has reported 9.8 million downloads of the e-mail client since then.
However, the foundation doesnt have an estimate of the number of people who are actively using Thunderbird, Scott MacGregor, Mozilla Thunderbird project lead engineer said Tuesday.
The release of the Plaxo toolbar "is a real testament to the success of Thunderbird" since it was released, MacGregor said.
"Its very exciting to see these things start to spring up around the Mozilla foundation, and it is something that we are trying to encourage," MacGregor said. Plaxo is "part of an evolving ecosystem of companies trying to get involved the Mozilla project," he said.
Since the Thunderbird code is all open-source, companies like Plaxo and major enterprise customers can readily write extensions for the e-mail client, said MacGregor.
One major enterprise vendor, which MacGregor declined to identify, has deployed 40,000 copies of Thunderbird and written custom extension for the e-mail client.
A Plaxo version for Thunderbird has been one of the most requested enhancements from both Plaxo and Thunderbird users, Masonis said.
Many Plaxo users have contacted the company and said they have wanted to switch to Thunderbird, but have been thwarted because Plaxo didnt run on that platform, Masonis said.
"We expect that a lot of people will hopefully be able to switch" to Thunderbird "because in some ways it is cleaner and simpler" to use than Outlook or Outlook Express, he said.
It has always been part of our strategy to support more than Outlook and Outlook Express, but thats what we started with," he said.
Plaxo is also developing a version of the contact manager for both the America Online Inc. e-mail platform and the instant messenger, which is due to go to beta test in a few months, so it will be ready for shipment by year end, Masonis said. This will make Plaxo available for AOLs 50 million e-mail subscribers, company officials said.