diff --git a/lib/db/upgrade.php b/lib/db/upgrade.php
index 4fc23fc1b38..9de60d5407a 100644
--- a/lib/db/upgrade.php
+++ b/lib/db/upgrade.php
@@ -1206,5 +1206,15 @@ function xmldb_main_upgrade($oldversion) {
         upgrade_main_savepoint(true, 2012090700.01);
     }
 
+    if ($oldversion < 2012092000.01) {
+        // Some folders still have a sortorder set, which is used for main files but is not
+        // supported by the folder resource. We reset the value here.
+        $sql = 'UPDATE {files} SET sortorder = ? WHERE component = ? AND filearea = ? AND sortorder <> ?';
+        $DB->execute($sql, array(0, 'mod_folder', 'content', 0));
+
+        // Main savepoint reached.
+        upgrade_main_savepoint(true, 2012092000.01);
+    }
+
     return true;
 }
diff --git a/version.php b/version.php
index a7954241884..593815a66c9 100644
--- a/version.php
+++ b/version.php
@@ -30,7 +30,7 @@
 defined('MOODLE_INTERNAL') || die();
 
 
-$version  = 2012092000.00;              // YYYYMMDD      = weekly release date of this DEV branch
+$version  = 2012092000.01;              // YYYYMMDD      = weekly release date of this DEV branch
                                         //         RR    = release increments - 00 in DEV branches
                                         //           .XX = incremental changes