Index: filefield.module
===================================================================
--- filefield.module	(revision 405)
+++ filefield.module	(working copy)
@@ -600,13 +600,28 @@
 
   // Update the cached form with the new element at the right place in the form.
   if (module_exists('fieldgroup') && ($group_name = _fieldgroup_field_get_group($type_name, $field_name))) {
+    $tree = _fieldgroup_get_tree($type_name);
+    $parents = array(0 => $group_name);
+    while ($group_name = $tree[$group_name]['parents'][0]) {
+      $parents[] = $group_name;
+    }
+    $parents = array_reverse($parents);
+
+    $element = $form;
+    foreach ($parents as $parent) {
+      $element = $element[$parent];
+    }
+
     if (isset($form['#multigroups']) && isset($form['#multigroups'][$group_name][$field_name])) {
-      $form_element = $form[$group_name][$delta][$field_name];
+      $form_element = $element[$delta][$field_name];
     }
     else {
-      $form_element = $form[$group_name][$field_name][$delta];
+      $form_element = $element[$field_name][$delta];
     }
   }
+  else {
+    $form_element = $form[$field_name][$delta];
+  }
 
   if (!isset($form_element)) {
     $form_element = $form[$field_name][$delta];