[Plugin: Explanatory Dictionary] A strange bug

I’ve got a strange new bug – I suspect webhosting modifying something but the result is strange.
When adding in my sidebar this code:

<h3>Top plugins</h3>
		<ul><li><?php query_posts("cat=18&posts_per_page=4"); ?>
<?php while ( have_posts() ) : the_post(); ?>
<a href="<?php the_permalink() ?>" rel="<?php the_title_attribute; ?>" alt="<?php the_title_attribute(); ?>"><?php the_excerpt(); ?></a>
<? endwhile; ?></li></ul>
<?php wp_reset_query(); ?>

the plugin just stops to work…

http://ww.wp.xz.cn/extend/plugins/explanatory-dictionary/