Comments stopped working after I upgraded to 4.0.3
/article/articlenr/articlename#cpreview
ANSWER:
Comments work fine in 4.0.3 if you’re using the standard comment form tags.
It seems some users have replaced their comment input form with hard-coded <input ... /> tags. This is incompatible with the new comment spam protection code in 4.0.3. See this forum thread for details.
The safest way to fix the problem is to replace your comment_form with the default. You can change the HTML markup in that form, but the <txp:comment... /> tags must be present.
See here for a brief explanation of the main comment tags and forms.
