dev #44524 fix fatal error

application/modules/admin/controllers/OuverturesController.php

@@ -94,8 +94,12 @@ class Admin_OuverturesController extends ZendAfi_Controller_Action {
     if(Class_Ouverture::AUCUN_JOUR != $post['jour_semaine'])
       $post['jour'] = null;
 
-    $post['validity_start'] = $this->_getSQLDateFrom($post['validity_start']);
-    $post['validity_end'] = $this->_getSQLDateFrom($post['validity_end']);
+    $post['validity_start'] = isset($post['validity_start'])
+      ? $this->_getSQLDateFrom($post['validity_start'])
+      : '';
+    $post['validity_end'] = isset($post['validity_end'])
+      ? $this->_getSQLDateFrom($post['validity_end'])
+      : '';
 
     return $post;
   }