Index: functions.php
===================================================================
--- functions.php	(revision 12782)
+++ functions.php	(working copy)
@@ -1708,12 +1708,14 @@
 
 	do_action( 'do_robotstxt' );
 
+	echo "User-agent: *\n";
+
 	if ( '0' == get_option( 'blog_public' ) ) {
-		echo "User-agent: *\n";
 		echo "Disallow: /\n";
 	} else {
-		echo "User-agent: *\n";
-		echo "Disallow:\n";
+		echo "Disallow: /wp-admin/\n";
+		echo "Disallow: /wp-includes/\n";
+		echo "Disallow: *?replytocom\n";
 	}
 }