diff --git a/core/modules/contact/contact.admin.inc b/core/modules/contact/contact.admin.inc
index 3e67ff8..9dd5af0 100644
--- a/core/modules/contact/contact.admin.inc
+++ b/core/modules/contact/contact.admin.inc
@@ -34,6 +34,10 @@ function contact_category_add() {
  */
 function contact_category_delete_form($form, &$form_state, Category $category) {
   $form_state['contact_category'] = $category;
+  $form['id'] = array(
+    '#type' => 'value',
+    '#value' => $category->id(),
+  );
   return confirm_form(
     $form,
     t('Are you sure you want to delete %label?', array('%label' => $category->label())),