[Plugin: WP-Paginate] Cannot Get To Work in Category Templates

Hi, I’ve WP Paginate working fine on my home.php page and search.php pages, but cannot get it to work on my category.php pages for specific categories.

My page loads okay, but when a page link in the pagination is clicked, I get a 404 error. Could anyone tell me what I am doing wrong? I use query_posts() to filter my queries on these pages.

Here’s an example of two loops on one of my pages:

<h2>Latest Events</h2>
<?php $events_query = new WP_Query("cat=4&showposts=5&paged=".$paged); // show 5 events posts only ?>
<?php if ($events_query->have_posts()) :  while ($events_query->have_posts()) : $events_query->the_post(); // start of loop ?>
<div class="post_preview" id="post-<?php the_ID(); ?>"><!-- post_preview -->
</div><!-- /post_preview -->
<?php endwhile; ?>
<?php if(function_exists('wp_paginate')) { wp_paginate(); } ?>
<?php else : endif; // end of loop ?>

Am I doing something obviously wrong here?

Any help would be much appreciated. Thanks, Mav3000.