diff --git a/interface/lib/classes/validate_autoresponder.inc.php b/interface/lib/classes/validate_autoresponder.inc.php
index ad0ee479be9404cf5d9ab2e28dfd923fc1b2da41..98d49fdf6d36bb43d61366690e903a3141e01f39 100755
--- a/interface/lib/classes/validate_autoresponder.inc.php
+++ b/interface/lib/classes/validate_autoresponder.inc.php
@@ -60,7 +60,7 @@ class validate_autoresponder extends validate_datetime
 		$end_date_tstamp = mktime($end_date_array['hour'], $end_date_array['minute'], $end_date_array['second'], $end_date_array['month'], $end_date_array['day'], $end_date_array['year']);
 		
 		// End date has to be > start date
-		if($end_date_tstamp <= $start_date_tstamp) {
+		if($end_date_tstamp <= $start_date_tstamp && ($start_date || $field_value)) {
 			return $app->tform->lng($validator['errmsg']).'<br />';
 		}
 	}