diff --git a/docs/newforms.txt b/docs/newforms.txt
index 5d49e83160..0b432e1b36 100644
--- a/docs/newforms.txt
+++ b/docs/newforms.txt
@@ -576,6 +576,11 @@ exception or returns the clean value::
     ...
     ValidationError: [u'Enter a valid e-mail address.']
 
+If you've used Django's old forms/validation framework, take care in noticing
+this ``ValidationError`` is different than the previous ``ValidationError``.
+This one lives at ``django.newforms.ValidationError`` rather than
+``django.core.validators.ValidationError``.
+
 Core field arguments
 --------------------