Mozilla wants to reproduce the Firefox Web browser's success with Thunderbird, its open-source e-mail software.

In 2005, the Mozilla Foundation set up a corporation to run elements of the Firefox Web browser operation. Now it's doing the same with Thunderbird, providing the as-yet-unnamed subsidiary with US$3 million and beginning plans to significantly expand its programming staff, said Mozilla Chief Executive Mitchell Baker.

"We're increasing Mozilla's focus with people and money, and we're hoping to use that to create something better, much as we do in the Firefox space ... for everyone interested in Internet and e-mail communications," Baker said.

David Ascher, currently chief technology officer at ActiveState and a longtime Mozilla community member, will become the new e-mail corporation's CEO.

Firefox, a rejuvenated incarnation of the original Netscape Navigator Web browser, has been a notable success in the open-source realm. Though it hasn't displaced Microsoft's Internet Explorer, it's attained significant market share. Last week, Mozilla said there had been 400 million official downloads of Firefox, an imperfect measure of its actual use but a notably large number nonetheless.

But reproducing the scale of Firefox's success won't be as easy with Thunderbird, RedMonk analyst Stephen O'Grady said. Microsoft's Outlook is tightly tied to its widely used Exchange e-mail server software, unlike the more easily swapped-out Web browser, and much of the new e-mail development is happening in Web-based services.

"They're unlikely to displace Outlook, of course, in Exchange settings, so they'll have to depend on convincing users of Gmail or ISP e-mail...that a mail client is necessary," O'Grady said.

The new corporation will draw the two or three dedicated Thunderbird programmers out from under their current Firefox umbrella and hire new staff, Baker said. As with its sister Mozilla Corp., the foundation set up the corporation as a convenient legal mechanism to meet overall Mozilla Foundation goals, not to be a moneymaking business, she added.

The dynamic nature of the e-mail business was on display this week when Yahoo, which operates a leading Web-based e-mail service, spent US$350 million to acquire Zimbra, which develops open-source software that gives Web-based e-mail much of the feel of PC-based e-mail software. Zimbra also offers an offline version that lets people read and write e-mail from computers when they're not connected to a network, further blurring the boundaries between Web- and PC-based e-mail software.

Ambitious vision
Ascher said the organisation's goal isn't to come up with an Outlook replacement, and he acknowledges the utility of Web-based e-mail. But a better e-mail client serves many people's needs, and conquering the entire world of e-mail isn't the group's agenda.

"Webmail is important, and I use it all the time, but I also use a desktop client. They work together," he said. "There's definitely lots of room for both. Because we're actually at the beginning doing this for the public interest, we don't need to have 100 percent of the market."

That's not to say Ascher doesn't have grand ambitions. His vision is of a unified inbox, and the new corporation's scope is consequently deliberately very broad: "Internet communications" rather than just e-mail.

"E-mail was the killer app of the Internet," but it isn't the only form of communication, Ascher said, pointing to Internet phone calls, RSS feeds for fetching blog updates, and text messages on mobile phones. "People end up subscribing to more and more channels of communications. It makes it hard to keep track of what's going on if they have to check six different inboxes, search across a variety of systems."

And, he adds, "Webmail is easy to check anywhere, but it doesn't make it easy to manage six different accounts."

Mozilla will look at usage statistics and improved software to gauge its success. Currently, Mozilla estimates that Thunderbird, first released in 2004, has between five million and ten million users.

Extending abilities through plug-ins
One feature that initially set Firefox apart from Internet Explorer was the fact that programmers could write new modules to extend the browser's abilities. Mozilla is working to reproduce the same vitality of the plug-in community work with Thunderbird, Ascher said.

"There is work to be done in the architecture to make it easier for developers to build those," he said. "Also, there's relatively superficial but important work to make it easier for users to find those."

The extensions work is well under way. Among those available today are Enigmail for encrypting e-mail, Webmail for harvesting e-mail from various Web-based e-mail sites, Send Later to send e-mails at a specified time in the future, Leet Key for geek-cred-enhancing text transformations, QuickMove to rapidly transfer e-mails to specified folders, and Contacts Sidebar to enable swifter access to addressees.

One big extension under development, called Penelope, endows Thunderbird with the interface of the venerable Eudora e-mail software from Qualcomm. A Penelope beta version is now available.

Stephen Shankland writes for CNET News.com

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