3 files changed, 17 insertions, 3 deletions
diff --git a/modules/system/system.admin.inc b/modules/system/system.admin.inc
index e352a60dc..a9f040f96 100644
--- a/modules/system/system.admin.inc
+++ b/modules/system/system.admin.inc
@@ -179,7 +179,9 @@ function system_themes_form() {
     }
     else {
       // Ensure this theme is compatible with this version of core.
-      if (!isset($theme->info['core']) || $theme->info['core'] != DRUPAL_CORE_COMPATIBILITY) {
+      // Require the 'content' region to make sure the main page 
+      // content has a common place in all themes.
+      if (!isset($theme->info['core']) || ($theme->info['core'] != DRUPAL_CORE_COMPATIBILITY) || (!isset($theme->info['regions']['content']))) {
         $incompatible_core[] = $theme->name;
       }
       if (version_compare(phpversion(), $theme->info['php']) < 0) {
@@ -1882,7 +1884,8 @@ function system_batch_page() {
   elseif (isset($output)) {
     // Force a page without blocks or messages to
     // display a list of collected messages later.
-    $page = drupal_get_page($output);
+    drupal_set_page_content($output);
+    $page = element_info('page');
     $page['#show_blocks'] = FALSE;
     $page['#show_messages'] = FALSE;
     return $page;
diff --git a/modules/system/system.install b/modules/system/system.install
index 9b8ab44d3..d0246fbc8 100644
--- a/modules/system/system.install
+++ b/modules/system/system.install
@@ -3347,7 +3347,7 @@ function system_update_7020() {
 }
 
 /**
- * Add help block to the help region, migrate custom variables to blocks.
+ * Add new blocks to new regions, migrate custom variables to blocks.
  */
 function system_update_7021() {
   $ret = array();
@@ -3359,6 +3359,8 @@ function system_update_7021() {
     $themes_with_blocks[] = $theme->name;
     // Add new system generated help block.
     $ret[] = update_sql("INSERT INTO {block} (module, delta, theme, status, weight, region, pages, cache) VALUES ('system', 'help', '" . $theme->name . "', 1, 0, 'help', '', 1)");
+    // Add new system generated main page content block.
+    $ret[] = update_sql("INSERT INTO {block} (module, delta, theme, status, weight, region, pages, cache) VALUES ('system', 'main', '" . $theme->name . "', 1, 0, 'content', '', -1)");
   }
 
   // Migrate contact form information.
diff --git a/modules/system/system.module b/modules/system/system.module
index 3f7c8521b..017c43473 100644
--- a/modules/system/system.module
+++ b/modules/system/system.module
@@ -878,6 +878,11 @@ function system_user_timezone(&$edit, &$form) {
  * Implementation of hook_block_list().
  */
 function system_block_list() {
+  $blocks['main'] = array(
+    'info' => t('Main page content'),
+     // Cached elsewhere.
+    'cache' => BLOCK_NO_CACHE,
+  );
   $blocks['powered-by'] = array(
     'info' => t('Powered by Drupal'),
     'weight' => '10',
@@ -946,6 +951,10 @@ function system_block_save($delta = '', $edit = NULL) {
 function system_block_view($delta = '') {
   $block = array();
   switch ($delta) {
+    case 'main':
+      $block['subject'] = NULL;
+      $block['content'] = drupal_set_page_content();
+      return $block;
     case 'powered-by':
       $image_path = 'misc/' . variable_get('drupal_badge_color', 'powered-blue') . '-' . variable_get('drupal_badge_size', '80x15') . '.png';
       $block['subject'] = NULL;