Index: modules/block/block.module
===================================================================
RCS file: /cvs/drupal/drupal/modules/block/block.module,v
retrieving revision 1.354
diff -u -p -r1.354 block.module
--- modules/block/block.module	4 Aug 2009 06:38:56 -0000	1.354
+++ modules/block/block.module	6 Aug 2009 01:50:17 -0000
@@ -514,7 +514,7 @@ function block_system_themes_form_submit
         }
       }
     }
-    if ($form_state['values']['admin_theme'] && $form_state['values']['admin_theme'] != variable_get('admin_theme', 0)) {
+    if ($form_state['values']['admin_theme'] && $form_state['values']['admin_theme'] !== variable_get('admin_theme', 0)) {
       // If we're changing themes, make sure the theme has its blocks initialized.
       $has_blocks = (bool) db_query_range('SELECT 1 FROM {block} WHERE theme = :theme', array(':theme' => $form_state['values']['admin_theme']), 0, 1)->fetchField();
       if (!$has_blocks) {