Fixing Math Comment Spam Protection Plugin in WordPress 3.0

Otto has an even better suggestion: use is_user_logged_in(). I have updated the recommended fix accordingly. Thanks, Otto!

As many people have noticed, the Math Comment Spam Protection plugin no longer works in WordPress 3.0. Unfortunately, the plugin appears to be no longer supported by its author, so some people are searching for an alternative plugin.

However, I have some good news: after a bit of trial-and-error, I found the problem with Math Comment Spam Protection. Even better news: the fix is incredibly simple.

Find Line 211 of math-comment-spam-protection.php:

if (  ( !isset($user_ID) ) && ( $comment_data['comment_type'] == '' ) ) { // Do not check if the user is registered & do not check trackbacks/pingbacks

The offending code is this:

( !isset($user_ID ))

Simply change the above to this (note: see update, above):

( ! $user_ID )

( ! is_user_logged_in() )

So that Line 211 looks like the following:

if (  ( ! $user_ID ) && ( $comment_data['comment_type'] == '' ) ) { // Do not check if the user is registered & do not check trackbacks/pingbacks

Voila! The Math Comment Spam Protection plugin will now work again!

This fix is so simple, I don't see any need to fork the code. I'll try to contact the developer, and see if he will patch the original.