I'm running WP 1.5 on a blog at http://a1great.com/, and am suddenly having issues with comments. I'm guessing that it's a permissions problem. (I am running another blog with comments enabled on this server, and am not experiencing any problems there.)
If you take a look at the URL above, and try to hit any comments area on the site, you'll see the errors I'm running into. Without pasting everything, it seems that I have something wrong with permissions in /wp-content/themes/default/comments.php and /wp-includes/comment-functions.php.
What are the proper permissions for these files and directories?