Tech Tip: WordPress 2.5 comments awaiting approval don’t appear in admin panel
If you find that comments awaiting moderation are not showing up in the admin panel of WordPress 2.5.x then you need the following fix to be applied to your WordPress database.
Use PHPMyAdmin or another too to connect to your WordPress database and issue the following SQL command:
create index comment_date_gmt on wp_comments(comment_date_gmt);
You should find that comments now display correctly in the admin panel.