Asa Dotzler writes "Our latest and greatest milestone release, Mozilla 1.4 Beta, is now available for download. This release features NTLM authentication support for Windows Mozilla users as well as a host of improvements to performance, stability, and site compatibility.
We've also posted the Mozilla 1.3.1 release which is intended to restore the XPInstall functionality that was missing in Mozilla 1.3 for Mac OS X. This is a minor bugfix release intended to bring OS X Mozilla up to feature parity with the Windows and Linux versions.
If you want to get your hands on new features like NTLM auth, improved pop-up blocking, improved junk-mail classification, improved performance and other goodness then you really want Mozilla 1.4 Beta rather than 1.3.1."