Acquia Drupal 1.2.21 (Drupal 6.15 core) contains new features, updates and bug fixes. The following list describes what is new in this version.

• Updated the Acquia Search package to 6.x-1.5180, which includes an update of the Apache Solr Search Integration module to 6.x-1.0-rc5. Note: this release includes an important performance fix.
• Updated the Image module to 6.x-1.0-beta4. Note: If you previously installed this module, you should rebuild all your image derivatives immediately prior to updating. This can be done by visiting Administer > Content management > Content (?q=admin/content/node), selecting items of type image, and running "Rebuild derivative images" on them. You also may see failed ALTER TABLE errors on update which can be ignored. After updating, you should clear all your caches by following the procedure in the "Notes" section below.

Notes:

• Acquia Drupal may include released, beta, alpha, or patched modules depending on which version is determined to be the most current, stable, secure and appropriate version for general use.
• Customers updating a production site should always perform a backup first, and, if possible, perform a trial update in a test environment before updating their production site.
• For some of the modules being upgraded, it is important to make sure that the new version of the module completely replaces the old one (i.e., that the entire module's directory is replaced and that there are no files from the old version left behind). Please follow the recommended upgrade procedures found in the Getting Started Guide.
• If you experience problems during the upgrade, clearing Drupal's caches may be necessary. You can do this by visiting Administer > Site configuration > Performance (?q=admin/settings/performance) and clicking the "Clear cached data" button at the bottom of the page. Also note that you may be prompted to run your site's database updates more than once, and if you see error messages during the upgrade they do not necessarily indicate a problem.