Question About Multiple Loop Conditional

I am attempting to dictate the number of post excerpts seen on category templates. I’m reading the multiple loop page in the codex, but not really understanding what I’m doing wrong. I have found this example:

// Get the last 10 posts in the special_cat category.
  <?php query_posts('category_name=special_cat&showposts=10'); ?>

  <?php while (have_posts()) : the_post(); ?>
    <!-- Do special_cat stuff... -->
  <?php endwhile;?>

I used this for the ‘special category’:

<?php query_posts('category_name=11&showposts=4'); ?>

but that returns a white page (just in the content area, the sidebars are fine).

I tried again using the rewind:

<?php rewind_posts(); ?>

still white page. help ?