Six months ago, Mozilla’s Asa Dotzler — one of the original members of the team that built the Firefox browser — made it quite clear that the open source outfit wasn’t interested in helping businesses. Their only aim, he said, was serve individual web surfers. “Enterprise has never been (and I’ll argue, shouldn’t be) a focus of ours,” Dotzler said.

But things have changed.

On Tuesday, Mozilla announced that it will answer the complaints of big business users, providing a new version of Firefox that it promises to support for a full year. This summer, the organization had switched Firefox to a six-week release cycle, and IT departments using the open source browser complained that they couldn’t keep up with the pace.

Mozilla calls the new version an extended support release, or ESR. The release will go through a 12-week testing cycle, and Mozilla says this will give businesses enough time to test early builds before deploying. The organization will then continue to provide support for the browser — i.e., security patches — for the rest of the year.

“With the implementation of the ESR plan, Mozilla continues its mission to provide the best Web experience for people everywhere, including those in companies, public institutions and organizations,” Kevin Needham, Mozilla’s channel manager, tells Wired over email. “The ESR is intended to provide groups responsible for managing their organization’s desktop environment with a version of Firefox that meets their testing and support requirements.”

After Google Chrome switched to a six-week release cycle, both Mozilla and Microsoft eventually followed suit, each reducing release cycles that often reached two years. When businesses using Firefox complained that the new “RapidRelease cycle didn’t leave them with enough time to properly test and certify each new browser — and that Mozilla stopped providing security patches for old versions much too soon — Asa Dotzler essentially told them to get over it. But Mozilla soon reversed its stance, and six months later, it has rubberstamped the ESR.

According to Mozilla’s ESR Proposal, starting on January 31st, the organization will begin testing Firefox 10. At the same time, it will offer an alpha version of ESR 10. The standard version of Firefox will move on to version 11. But after 12 weeks of testing ESR 10.0.0 and ESR 10.0.1, Mozilla will officially released ESR 10, and this will remain available through the end of the year.

Twelve weeks before the end of that year, the organization will begin testing ESR 17, and the process will start all over again. ESR 24 is then slated for testing in September 2013.

For now, the ERP program does not include Firefox mobile, nor Mozilla’s other major open-source application, Thunderbird, an email client. But Mozilla has created an enterprise discussion group for the email client.