unique fields won't be validated by .is_valid() in NewForms form_for_models

[packermann@…]

I have some unique-Fields in my models.py. I use form_for_models and form_for_instance to build my forms to populate my DB. For validation I use .is_valid():
Example:

if request.method == 'POST':
		f = ServerForm(request.POST)
		if f.is_valid():
			saveobject = f.save()

If I test this by trying to add a duplicate entry, I get a "duplicate key violates unique constraint" instead of the expected error-message in my forms as for the other validation.
If you need some files, traceback please mail me.

regards

[Brian Rosner]

I am closing this as a duplicate of #4895. The reasoning in that ticket is the same for this one as well.