? .settings
Index: modules/field/field.api.php
===================================================================
RCS file: /cvs/drupal/drupal/modules/field/field.api.php,v
retrieving revision 1.68
diff -u -p -r1.68 field.api.php
--- modules/field/field.api.php	26 Mar 2010 17:14:45 -0000	1.68
+++ modules/field/field.api.php	26 Mar 2010 23:51:40 -0000
@@ -1589,12 +1589,12 @@ function hook_field_delete_field($field)
  * This hook is invoked after the instance record is saved and so it cannot
  * modify the instance itself.
  *
- * TODO: Not implemented.
- *
  * @param $instance
- *   The instance just updated.
+ *   The instance as it is post-update.
+ * @param $prior_$instance
+ *   The instance as it was pre-update.
  */
-function hook_field_update_instance($instance) {
+function hook_field_update_instance($instance, $prior_instance) {
 }
 
 /**
Index: modules/field/field.crud.inc
===================================================================
RCS file: /cvs/drupal/drupal/modules/field/field.crud.inc,v
retrieving revision 1.53
diff -u -p -r1.53 field.crud.inc
--- modules/field/field.crud.inc	3 Mar 2010 07:56:18 -0000	1.53
+++ modules/field/field.crud.inc	26 Mar 2010 23:49:43 -0000
@@ -700,6 +700,8 @@ function field_update_instance($instance
 
   // Clear caches.
   field_cache_clear();
+
+  module_invoke_all('field_update_instance', $instance, $prior_instance);
 }
 
 /**