diff --git a/interface/lib/classes/tform_actions.inc.php b/interface/lib/classes/tform_actions.inc.php
index c46537e39015e303ea7aca9df3ca754a9fa1a1ad..91b063ae3a42c49200825f66b051eeae6f38049d 100644
--- a/interface/lib/classes/tform_actions.inc.php
+++ b/interface/lib/classes/tform_actions.inc.php
@@ -118,7 +118,7 @@ class tform_actions {
 				if($_SESSION["s"]["form"]["return_to"] != '') {
 					$list_name = $_SESSION["s"]["form"]["return_to"];
 					$redirect = "Location: ".$_SESSION["s"]["list"][$list_name]["parent_script"]."?id=".$_SESSION["s"]["list"][$list_name]["parent_id"]."&next_tab=".$_SESSION["s"]["list"][$list_name]["parent_tab"];
-					unset($_SESSION["s"]["form"]["return_to"]);
+					$_SESSION["s"]["form"]["return_to"] = '';
 					header($redirect);
 				} else {
     				header("Location: ".$app->tform->formDef['list_default']);
@@ -155,7 +155,7 @@ class tform_actions {
     			if($_SESSION["s"]["form"]["return_to"] != '') {
 					$list_name = $_SESSION["s"]["form"]["return_to"];
 					$redirect = "Location: ".$_SESSION["s"]["list"][$list_name]["parent_script"]."?id=".$_SESSION["s"]["list"][$list_name]["parent_id"]."&next_tab=".$_SESSION["s"]["list"][$list_name]["parent_tab"];
-					unset($_SESSION["s"]["form"]["return_to"]);
+					$_SESSION["s"]["form"]["return_to"] = '';
 					header($redirect);
 				} else {
     				header("Location: ".$app->tform->formDef['list_default']);
@@ -237,7 +237,7 @@ class tform_actions {
 		if($_SESSION["s"]["form"]["return_to"] != '') {
 			$list_name = $_SESSION["s"]["form"]["return_to"];
 			$redirect = "Location: ".$_SESSION["s"]["list"][$list_name]["parent_script"]."?id=".$_SESSION["s"]["list"][$list_name]["parent_id"]."&next_tab=".$_SESSION["s"]["list"][$list_name]["parent_tab"];
-			unset($_SESSION["s"]["form"]["return_to"]);
+			$_SESSION["s"]["form"]["return_to"] = '';
 			header($redirect);
 		} else {
     		header("Location: ".$liste["file"]);