diff --git a/wp-includes/canonical.php b/wp-includes/canonical.php
index 453641a2b7..14d60797a1 100644
--- a/wp-includes/canonical.php
+++ b/wp-includes/canonical.php
@@ -218,7 +218,10 @@ function redirect_canonical( $requested_url = null, $do_redirect = true ) {
 				$addl_path = !empty( $addl_path ) ? trailingslashit($addl_path) : '';
 				if ( get_query_var( 'withcomments' ) )
 					$addl_path .= 'comments/';
-				$addl_path .= user_trailingslashit( 'feed/' . ( ( get_default_feed() ==  get_query_var('feed') || 'feed' == get_query_var('feed') ) ? '' : get_query_var('feed') ), 'feed' );
+				if( (in_array( get_default_feed(), array( 'rss', 'rdf' ) ) && 'feed' == get_query_var('feed')) || in_array( get_query_var('feed'), array( 'rss', 'rdf' ) ) )
+					$addl_path .= user_trailingslashit( 'feed/' . ( ( get_default_feed() == 'rss2' ) ? '' : 'rss2' ), 'feed' );
+				else
+					$addl_path .= user_trailingslashit( 'feed/' . ( ( get_default_feed() ==  get_query_var('feed') || 'feed' == get_query_var('feed') ) ? '' : get_query_var('feed') ), 'feed' );
 				$redirect['query'] = remove_query_arg( 'feed', $redirect['query'] );
 			}
 
@@ -295,6 +298,9 @@ function redirect_canonical( $requested_url = null, $do_redirect = true ) {
 		// Clean up empty query strings
 		$redirect['query'] = trim(preg_replace( '#(^|&)(p|page_id|cat|tag)=?(&|$)#', '&', $redirect['query']), '&');
 
+		// Redirect obsolete feeds
+		$redirect['query'] = preg_replace( '#(^|&)feed=(rss|rdf)(&|$)#', '$1feed=rss2$3', $redirect['query'] );
+
 		// Remove redundant leading ampersands
 		$redirect['query'] = preg_replace( '#^\??&*?#', '', $redirect['query'] );
 	}
diff --git a/wp-includes/feed.php b/wp-includes/feed.php
index b94e34766d..d76ad769a3 100644
--- a/wp-includes/feed.php
+++ b/wp-includes/feed.php
@@ -63,7 +63,8 @@ function bloginfo_rss($show = '') {
  * @return string Default feed, or for example 'rss2', 'atom', etc.
  */
 function get_default_feed() {
-	return apply_filters('default_feed', 'rss2');
+	$default_feed = apply_filters('default_feed', 'rss2');
+	return in_array( $default_feed, array( 'rss', 'rdf' ) ) ? 'rss2' : $default_feed;
 }
 
 /**