Index: pluggable.php
===================================================================
--- pluggable.php	(revision 21177)
+++ pluggable.php	(working copy)
@@ -1256,6 +1256,8 @@
 function wp_verify_nonce($nonce, $action = -1) {
 	$user = wp_get_current_user();
 	$uid = (int) $user->ID;
+	if ( empty( $uid ) )
+		$uid = $_SERVER[ 'REMOTE_ADDR' ] . $_SERVER[ 'HTTP_USER_AGENT' ];
 
 	$i = wp_nonce_tick();
 
@@ -1282,6 +1284,8 @@
 function wp_create_nonce($action = -1) {
 	$user = wp_get_current_user();
 	$uid = (int) $user->ID;
+	if ( empty( $uid ) )
+		$uid = $_SERVER[ 'REMOTE_ADDR' ] . $_SERVER[ 'HTTP_USER_AGENT' ];
 
 	$i = wp_nonce_tick();