Some days later of the Beta 3 release the Beta 4 of Drupal 6.0 has been released, they hope to release the first Release Candidate if no more critical bugs are found on this beta, so, Drupal users please start testing it and reporting bugs.

According to Drupal these are the changes and fixes in this new release

Changes made since the release of Drupal 6.0 beta 3 include several multilingual support fixes, caching improvements, more clear help texts, drag and drop support for book outlines, user profile administration, taxonomy pages and file uploads, and fixes to node teaser generation. With the right to left version of the pushbutton theme, we also completed RTL support for all core themes. We have also hardened the security of the system, closing potential cross site scripting (XSS) and cross site request forgery (CSRF) security holes. This beta release also includes the security updates released in Drupal 5.4 and 4.7.9

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