After six months of development, the Drupal team is proud to announce the Drupal 4.6.0 release! Thanks to those who contributed to this release, either by contributing code, testing the release candidate, providing support or writing documentation.
The key changes since Drupal 4.5 include:
- PHP5 support.
- Better search usability, improved results and relevancy.
- Personal contact forms for registered users.
- Improved multi-site support to run multiple
- Drupal sites from a single code base.
- Extensible RSS 2.0 syndication support for enclosures (e.g. podcasts) and categories.
- Ping Ping-O-Matic, to ping all major ping services.
- Usability improvements for permissions, block configuration, statistics tracking, logs, forum configuration, content administration, etc.
For a complete list, please consult the CHANGELOG . In addition to all of the above, we made significant improvements under the hood in terms of performance and better APIs. Contributed themes and modules  have already begun to take advantage of these.
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