Index: wp-includes/class-feed.php
===================================================================
--- wp-includes/class-feed.php	(revision 22594)
+++ wp-includes/class-feed.php	(working copy)
@@ -3,9 +3,6 @@
 if ( !class_exists('SimplePie') )
 	require_once (ABSPATH . WPINC . '/class-simplepie.php');
 
-if ( version_compare( SIMPLEPIE_VERSION, '1.3-dev', '>' ) ) :
-	SimplePie_Cache::register( 'wp-transient', 'WP_Feed_Cache_Transient' );
-else :
 	class WP_Feed_Cache extends SimplePie_Cache {
 		/**
 		 * Create a new SimplePie_Cache object
@@ -17,7 +14,6 @@
 			return new WP_Feed_Cache_Transient($location, $filename, $extension);
 		}
 	}
-endif;
 
 class WP_Feed_Cache_Transient {
 	var $name;
Index: wp-includes/feed.php
===================================================================
--- wp-includes/feed.php	(revision 22594)
+++ wp-includes/feed.php	(working copy)
@@ -528,14 +528,8 @@
 
 	$feed = new SimplePie();
 
-	if ( version_compare( SIMPLEPIE_VERSION, '1.3-dev', '>' ) ) {
-		$feed->set_cache_location( 'wp-transient' );
-		$feed->registry->register( 'Cache', 'WP_Feed_Cache_Transient' );
-		$feed->registry->register( 'File', 'WP_SimplePie_File' );
-	} else {
-		$feed->set_cache_class( 'WP_Feed_Cache' );
-		$feed->set_file_class( 'WP_SimplePie_File' );
-	}
+	$feed->set_cache_class( 'WP_Feed_Cache' );
+	$feed->set_file_class( 'WP_SimplePie_File' );
 
 	$feed->set_feed_url($url);
 	$feed->set_cache_duration( apply_filters( 'wp_feed_cache_transient_lifetime', 12 * HOUR_IN_SECONDS, $url ) );