Qualcomm on Wednesday joined up with the Mozilla Foundation to announce it is transitioning Eudora into an open source e-mail client that will be based upon Thunderbird. In turn, all future versions of Eudora will be free and Qualcomm will discontinue the current paid client.

Although it may seem like Eudora is simply abandoning its e-mail software, which has a small but strong following of loyal users, the company claims the Thunderbird-based client will retain "Eudora's uniquely rich feature set and productivity enhancements."

Current Eudora users can choose to keep running the ad-supported version indefinitely after upgrading to version 7.1 for Windows and 6.2.4 for Mac OS X, released last week but announced only today. Qualcomm says it will stop displaying advertisements in the client sometime early next year.

"Qualcomm has decided not to remain in the email market because it is not in alignment with the core business or strategic goals," the company said. "By moving Eudora to an open source product, Qualcomm can exit the Eudora business while still supporting Eudora users and advancing the Eudora e-mail client at a faster pace than before, through the power of the open source development community."

"We're pleased to welcome Eudora and its millions of users to the world of open source," said Frank Hecker, executive director of the Mozilla Foundation. "This effort should further enrich the Thunderbird technology platform and provide users of both products with an even richer email experience."

In recent months, reviewers continued to give Eudora the performance edge for use with enterprise e-mail, compared against Thunderbird (though not against Microsoft Outlook). However, in practice, some have noted Eudora has suffered limited performance problems with recent versions, prompting in at least one case suggestions that users (in this case, students) try Thunderbird instead.