Ticket #18609: 18609.diff

src/wp-includes/ms-functions.php

@@ -2127 +2127 @@
                         update_option( 'default_category', $global_id );
                 }
 
-                $wpdb->update( $wpdb->terms, array( 'term_id' => $global_id ), array( 'term_id' => $term_id ) );
+                if ( $global_id < $max_local_id ) {
+                        $wpdb->update( $wpdb->terms, array( 'term_id' => $global_id ), array( 'term_id' => $term_id ) );
+                } else {
+                        $wpdb->delete( $wpdb->terms, array( 'term_id' => $term_id ) );
+                        $c            = (array) $c;
+                        $c['term_id'] = $global_id;
+                        $wpdb->insert( $wpdb->terms, $c );
+                }
+
                 $wpdb->update( $wpdb->term_taxonomy, array( 'term_id' => $global_id ), array( 'term_id' => $term_id ) );
                 $wpdb->update( $wpdb->term_taxonomy, array( 'parent' => $global_id ), array( 'parent' => $term_id ) );