Mozilla has released Thunderbird 1.5, the latest version of its full-featured email client for OS X.

The software is available for free download. The release is the culmination of a year's worth of user feedback.

"With a host of new and improved features, Thunderbird 1.5 provides users with a robust, free email alternative," said Christopher Beard, vice president of products at Mozilla: "Thunderbird enhances the overall email experience, adding anti-phishing capabilities to help keep people safer, while also integrating and simplifying access to new technologies, such as RSS (Really Simple Syndication)."

New features include automatic software updates; much-improved spam filters; built-in phishing detection; spell checkers and more.

Thunderbird's RSS support lets users receive RSS feed updates as email messages, filtering and organizing them as it would ordinary email. Thunderbird 1.5 also allows users to access podcasts.