? sites/default/files
? sites/default/private
? sites/default/settings.php
Index: modules/system/system.module
===================================================================
RCS file: /cvs/drupal/drupal/modules/system/system.module,v
retrieving revision 1.766
diff -u -p -r1.766 system.module
--- modules/system/system.module	24 Aug 2009 00:14:22 -0000	1.766
+++ modules/system/system.module	24 Aug 2009 09:39:09 -0000
@@ -3075,6 +3075,21 @@ function system_retrieve_file($url, $des
  * Implement hook_page_alter().
  */
 function system_page_alter(&$page) {
+  // If no module has populated any region of the page, provide a fallback
+  // implementation which inserts the main page content into the "content"
+  // region. This allows the site to still be usable even if no modules that
+  // control page regions (for example, the Block module) are enabled.
+  global $theme_key;
+  $region_list = system_region_list($theme_key, REGIONS_VISIBLE);
+  foreach ($region_list as $region => $value) {
+    if(!empty($page[$region])) {
+      $region_filled = true;
+    }
+  }
+  if (!isset($region_filled)) {
+    $page['content'] = drupal_set_page_content();
+  }
+
   // Automatic cron runs.
   // @see system_run_cron_image()
   if (system_run_cron_image_access()) {