Index: modules/system/system.module
===================================================================
RCS file: /cvs/drupal/drupal/modules/system/system.module,v
retrieving revision 1.676
diff -u -r1.676 system.module
--- modules/system/system.module	25 Mar 2009 18:40:50 -0000	1.676
+++ modules/system/system.module	3 Apr 2009 02:27:24 -0000
@@ -2323,3 +2323,18 @@
     ),
   );
 }
+
+/**
+ * Implementation of hook_modules_uninstalled().
+ */
+function system_modules_uninstalled($modules) {
+  foreach($modules as $module){
+    // Retrieve and delete all the module's actions.
+    drupal_load('module', $module);
+    if ($actions = module_invoke($module, 'action_info')) {
+      foreach($actions as $aid => $action){
+        actions_delete($aid);
+      }
+    }
+  }
+}