diff --git a/plugins/managesieve/managesieve.js b/plugins/managesieve/managesieve.js
index 8340b179d..4d60833be 100644
--- a/plugins/managesieve/managesieve.js
+++ b/plugins/managesieve/managesieve.js
@@ -736,6 +736,9 @@ function smart_field_init(field)
 
   if (field.attr('disabled'))
     area.hide();
+  // disable the original field anyway, we don't want it in POST
+  else
+    field.prop('disabled', true);
 
   field.after(area);