Index: wp-admin/admin-ajax.php
===================================================================
--- wp-admin/admin-ajax.php	(revision 7508)
+++ wp-admin/admin-ajax.php	(working copy)
@@ -371,7 +371,7 @@
 	check_ajax_referer( 'add-meta' );
 	$c = 0;
 	$pid = (int) $_POST['post_id'];
-	if ( isset($_POST['metakeyselect']) ) {
+	if ( isset($_POST['metakeyselect']) || isset($_POST['metakeyinput']) ) {
 		if ( !current_user_can( 'edit_post', $pid ) )
 			die('-1');
 		if ( '#NONE#' == $_POST['metakeyselect'] && empty($_POST['metakeyinput']) )