Index: wp-login.php
===================================================================
--- wp-login.php	(revision 15344)
+++ wp-login.php	(working copy)
@@ -190,7 +190,7 @@
 	$message .= network_site_url() . "\r\n\r\n";
 	$message .= sprintf(__('Username: %s'), $user_login) . "\r\n\r\n";
 	$message .= __('To reset your password visit the following address, otherwise just ignore this email and nothing will happen.') . "\r\n\r\n";
-	$message .= network_site_url("wp-login.php?action=rp&key=$key&login=" . rawurlencode($user_login), 'login') . "\r\n";
+	$message .= '<' . network_site_url("wp-login.php?action=rp&key=$key&login=" . rawurlencode($user_login), 'login') . '>' . "\r\n";
 
 	if ( is_multisite() )
 		$blogname = $GLOBALS['current_site']->site_name;