Index: wp-includes/option.php
===================================================================
--- wp-includes/option.php	(revision 21550)
+++ wp-includes/option.php	(working copy)
@@ -491,7 +491,8 @@
 function set_transient( $transient, $value, $expiration = 0 ) {
 	global $_wp_using_ext_object_cache;
 
-	$value = apply_filters( 'pre_set_transient_' . $transient, $value );
+	$value = apply_filters( 'pre_set_transient_' . $transient, $value, $expiration );
+	$expiration = apply_filters( 'expiration_pre_set_transient_' . $transient, $expiration, $value );
 
 	if ( $_wp_using_ext_object_cache ) {
 		$result = wp_cache_set( $transient, $value, 'transient', $expiration );
@@ -1021,7 +1022,8 @@
 function set_site_transient( $transient, $value, $expiration = 0 ) {
 	global $_wp_using_ext_object_cache;
 
-	$value = apply_filters( 'pre_set_site_transient_' . $transient, $value );
+	$value = apply_filters( 'pre_set_site_transient_' . $transient, $value, $expiration );
+	$expiration = apply_filters( 'expiration_pre_set_site_transient_' . $transient, $expiration, $value );
 
 	if ( $_wp_using_ext_object_cache ) {
 		$result = wp_cache_set( $transient, $value, 'site-transient', $expiration );