Index: wp-content/themes/twentyeleven/inc/theme-options.php
===================================================================
--- wp-content/themes/twentyeleven/inc/theme-options.php	(revision 18313)
+++ wp-content/themes/twentyeleven/inc/theme-options.php	(working copy)
@@ -162,7 +162,7 @@
 	$default_theme_options = array(
 		'color_scheme' => 'light',
 		'link_color'   => twentyeleven_get_default_link_color( 'light' ),
-		'theme_layout' => 'content-sidebar',
+		'theme_layout' => is_rtl() ? 'sidebar-content' : 'content-sidebar',
 	);
 
 	return apply_filters( 'twentyeleven_default_theme_options', $default_theme_options );