As I was creating a page template for wordpress, I wanted to list posts from a specific category on a page when I ran into a interesting problem, the query_posts function I was using was causing breaks in the execution of conditional tags like is_page(’25′) in the sidebar template.  I looked around on the web for a while before finally finding the solution that worked for me. So I am rewriting the solution here for reference and so anyone else may find it easier.

Here is how you list posts from a particular category in a wordpress page template, right before the “while (have_posts()) : the_post(); ” call add:

<?php query_posts('category_name=name&showposts=100'); ?>
<?php /*  change name to the name of the category posts you want to display   */  ?>

The reason the wordpress function query_posts() breaks the sidebar template is because its not a simple database query collecting posts from a specific category, but its resetting the query object as a whole to reflect a normal category query.

So to fix the sidebar template you have to go with creating a new query object through WP_Query() in your page template. So here is the before and after of the loop in a page template.

Page Template Loop BEFORE:

<?php query_posts('category_name=name&showposts=100'); ?>
<?php while (have_posts()) : the_post(); ?>
       <!-- do stuff ... -->
<?php endwhile; ?>

Page Template Loop AFTER:

<?php $cat_posts = new WP_Query('category_name=name'); ?>
<?php if($cat_posts->have_posts()) : ?>
         <?php while($cat_posts->have_posts()) : $cat_posts->the_post(); ?>
                 <!-- do stuff ... -->
         <?php endwhile; ?>
<?php endif; ?>

Hope that helps someone, cya.