Index: wp-includes/taxonomy.php
===================================================================
--- wp-includes/taxonomy.php	(revision 25052)
+++ wp-includes/taxonomy.php	(working copy)
@@ -466,13 +466,13 @@
  * @param string $object_type Name of the object type
  * @return bool True if successful, false if not
  */
-function register_taxonomy_for_object_type( $taxonomy, $object_type) {
+function register_taxonomy_for_object_type( $taxonomy, $object_type ) {
 	global $wp_taxonomies;
 
-	if ( !isset($wp_taxonomies[$taxonomy]) )
+	if ( ! isset( $wp_taxonomies[$taxonomy] ) )
 		return false;
 
-	if ( ! get_post_type_object($object_type) )
+	if ( ! get_post_type_object( $object_type ) )
 		return false;
 
 	if ( ! in_array( $object_type, $wp_taxonomies[$taxonomy]->object_type ) )
@@ -481,6 +481,34 @@
 	return true;
 }
 
+/**
+ * Remove an already registered taxonomy from an object type.
+ *
+ * @package WordPress
+ * @subpackage Taxonomy
+ * @since 3.7.0
+ * @uses $wp_taxonomies Modifies taxonomy object
+ *
+ * @param string $taxonomy Name of taxonomy object
+ * @param string $object_type Name of the object type
+ * @return bool True if successful, false if not
+ */
+function unregister_taxonomy_from_object_type( $taxonomy, $object_type ) {
+	global $wp_taxonomies;
+
+	if ( ! isset( $wp_taxonomies[$taxonomy] ) )
+		return false;
+
+	foreach ( array_keys( $wp_taxonomies[$taxonomy]->object_type ) as $array_key ) {
+		if ( $wp_taxonomies[$taxonomy]->object_type[$array_key] === $object_type ) {
+			unset( $wp_taxonomies[$taxonomy]->object_type[$array_key] );
+			return true;
+		}
+	}
+	
+	return false;
+}
+
 //
 // Term API
 //