Index: wp-includes/canonical.php
===================================================================
--- wp-includes/canonical.php	(revision 6322)
+++ wp-includes/canonical.php	(working copy)
@@ -4,7 +4,7 @@
 function redirect_canonical($requested_url=NULL, $do_redirect=true) {
 	global $wp_rewrite, $posts, $is_IIS;
 
-	if ( is_feed() || is_trackback() || is_search() || is_comments_popup() || is_admin() || $is_IIS || ( isset($_POST) && count($_POST) ) || is_preview() )
+	if ( is_feed() || is_trackback() || is_search() || is_comments_popup() || is_admin() || $is_IIS || ( isset($_POST) && count($_POST) ) || is_preview()|| is_empty() )
 		return;
 
 	if ( !$requested_url ) {
@@ -198,4 +198,4 @@
 
 add_action('template_redirect', 'redirect_canonical');
 
-?>
\ No newline at end of file
+?>
Index: wp-includes/query.php
===================================================================
--- wp-includes/query.php	(revision 6322)
+++ wp-includes/query.php	(working copy)
@@ -216,6 +216,11 @@
 	return false;
 }
 
+function is_empty () {
+        global $wp_query;
+        return empty($post);
+}
+
 function is_singular() {
 	global $wp_query;