diff --git a/wp-admin/includes/upgrade.php b/wp-admin/includes/upgrade.php
index 4cd481ed81..c21f951b3f 100644
--- a/wp-admin/includes/upgrade.php
+++ b/wp-admin/includes/upgrade.php
@@ -442,6 +442,9 @@ function upgrade_all() {
 	if ( $wp_current_db_version < 29630 )
 		upgrade_400();
 
+	if ( $wp_current_db_version < 30056 )
+		upgrade_410();
+
 	maybe_disable_link_manager();
 
 	maybe_disable_automattic_widgets();
@@ -1328,6 +1331,18 @@ function upgrade_400() {
 	}
 }
 
+/**
+ * Execute changes made in WordPress 4.1.0.
+ *
+ * @since 4.1.0
+ */
+function upgrade_410() {
+	global $wp_current_db_version, $wpdb;
+	if ( $wp_current_db_version < 30056 ) {
+		add_clean_index( $wpdb->terms, 'slug' );
+	}
+}
+
 /**
  * Execute network level changes
  *
diff --git a/wp-includes/version.php b/wp-includes/version.php
index 6372807091..22fb6137b0 100644
--- a/wp-includes/version.php
+++ b/wp-includes/version.php
@@ -4,14 +4,14 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.1-alpha-30120';
+$wp_version = '4.1-alpha-30121';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.
  *
  * @global int $wp_db_version
  */
-$wp_db_version = 29630;
+$wp_db_version = 30056;
 
 /**
  * Holds the TinyMCE version