Following Mozilla Firefox 1.5 Beta 1 which just recently released couple days ago, today Mozilla released Thunderbird 1.5 Beta 1. Mozilla Thunderbird is a light-weight open-source email client, with support for RSS feed and newsgroup. Similar to Firefox, this more-secure-than-outlook email client’s features can be extended via extension.

I haven’t tried this beta version, but I hope this one fixes the progress bar glitch when receiving or sending email.

What’s new on Thunderbird 1.5 Beta 1:

• Automated update to streamline product upgrades. Notification of an update is more prominent, and updates to Thunderbird may now be half a megabyte or smaller. Updating extensions has also improved.
• Spell check as you type.
• Built in phishing detector to help protect users against email scams.
• Podcasting and other RSS Improvements.
• Deleting attachments from messages.
• Integration with server side spam filtering.
• Reply and forward actions for message filters.
• Kerberos Authentication.
• Auto save as draft for mail composition.
• Improvements to product usability including redesigned options UI, and SMTP server management.
• Many security enhancements

You can download Thunderbird 1.5 Beta 1 here: Windows, Linux, Mac OS X.