[Plugin: AJAX Comment Loading] New comments not showing with the plugin active

This is the code I use to display the comment form:

<?php
	$args = array(
		'comment_notes_before' => '<p>So you\'ve decided to leave a comment, ha! That\'s great. Please keep in mind that comments are strictly moderated. You may use your name or nickname, but refrain from spamming (including keyword or a domain as your name, links in signature), or your comment(s) will be deleted. Thanks for stopping by!</p>',
		'fields' => array(
						'author' => '<p class="comment-form-author">' . '<label for="author">' . __( 'Name' ) . '</label> ' . ( $req ? '<span class="required">(required)</span>' : '' ) . '<input id="author" name="author" type="text" value="' . esc_attr( $commenter['comment_author'] ) . '" size="50"' . ' /></p>',
						'email' => '<p class="comment-form-email"><label for="email">' . __( 'Email' ) . '</label> ' . ( $req ? '<span class="required">(required, not published)</span>' : '' ) . '<input id="email" name="email" type="text" value="' . esc_attr(  $commenter['comment_author_email'] ) . '" size="50"' . ' /></p>'
		),
		'comment_notes_after' => '<p class="form-allowed-tags">' . sprintf( __( 'You may use these <abbr title="HyperText Markup Language">HTML</abbr> tags to format your comments (please don\'t overuse them): %s' ), ' <code><b></code> <code><i></code> <code><strong></code> <code><em></code> <code><a href=""></code> <code><blockquote></code> <code><strike></code> <code><del></code>' ) . '</p>'
	);
	comment_form( $args );
?>

I simply activated the plugin, and made two comments. The comments didn’t show up. I checked, they were not detected as spam either.

Then I deactivated the plugin, and the comments showed up. Then I activated the plugin again, and the comments are gone again. Any idea why?

http://wordpress.org/extend/plugins/ajax-comment-loading/