For some reason, I couldn't validate my feeds with the FeedValidator? because a single quote character was being encoded the ′ entity character. Seems like that would be fine, but for some reason, it wouldn't validate. Also, Firefox couldn't display my RSS2 feed properly either because of the ′ entity character. So, I made the following changes which fixed the problem. By the way, I made this change in WP 1.2.
File: /wp-includes/functions-formatting.php
Old:
Line 25: $curl = preg_replace('/(\d+)"/', '$1″', $curl);
Line 26: $curl = preg_replace("/(\d+)'/", '$1′', $curl);
New:
Line 25: $curl = preg_replace('/(\d+)"/', '$1″', $curl);
Line 26: $curl = preg_replace("/(\d+)'/", '$1′', $curl);`
