Index: wp-includes/template-loader.php
===================================================================
--- wp-includes/template-loader.php	(revision 18473)
+++ wp-includes/template-loader.php	(working copy)
@@ -40,7 +40,7 @@
 		$template = get_index_template();
 	endif;
 	if ( $template = apply_filters( 'template_include', $template ) )
-		include( $template );
+		load_template( $template, false );
 	return;
 endif;