Index: filefield.module
===================================================================
RCS file: /cvs/drupal-contrib/contributions/modules/filefield/filefield.module,v
retrieving revision 1.192
diff -u -r1.192 filefield.module
--- filefield.module	13 Apr 2009 00:53:51 -0000	1.192
+++ filefield.module	13 Apr 2009 04:11:03 -0000
@@ -484,7 +484,8 @@
 
   if (empty($field) || empty($_POST['form_build_id'])) {
     // Invalid request.
-    print drupal_to_js(array('data' => ''));
+    drupal_set_message(t('An unrecoverable error occurred. The uploaded file likely exceeded the maximum file size (@size) that this server supports.', array('@size' => format_size(file_upload_max_size()))), 'error');
+    print drupal_to_js(array('data' => theme('status_messages')));
     exit;
   }
 
@@ -495,7 +496,8 @@
 
   if (!$form) {
     // Invalid form_build_id.
-    print drupal_to_js(array('data' => ''));
+    drupal_set_message(t('An unrecoverable error occurred. This form was missing from the server cache. Try reloading the page and submitting again.'), 'error');
+    print drupal_to_js(array('data' => theme('status_messages')));
     exit;
   }