Viewing previous post pages displays same post.

I have themed a blog for a friend http://www.kertasyofyou.com/home/

& i am having an issue with it. At the very bottom of the ag when you click to go back to view the previous blog entries. the enteries to dont change so when you click to go to lets say “page 2” the same enteries on the main page show up & its the same for every page you go back. I don’t know whats causing it. & thought maybe someone else could help me out. the code on my index.php page is this

<?php get_header(); ?>

<div id="side-left">

	<div id="content">

<?php query_posts('cat=-11'); ?>

<?php if ( have_posts() ) : while  ( have_posts() ) : the_post(); ?>

		<div class="kutu">

	<div class="ust"><span></span></div>

			<div class="post" id="post-<?php the_ID(); ?>">

				<h2><a href="<?php the_permalink() ?>" rel="bookmark" title="<?php the_title_attribute(); ?> için Kalıcı Bağlantı"><?php the_title(); ?></a></h2>

				<div class="tags"><?php the_tags('Tags: ', ', ', ''); ?></div>

				<div class="entry">

					<?php the_content('Read More>>'); ?>

<br><br>

<center>

SHARE:
<?php if( function_exists('ADDTOANY_SHARE_SAVE_KIT') ) { ADDTOANY_SHARE_SAVE_KIT(); } ?>
</center>

</div>

		<br class="clear" />

				<div class="postmetadata">

<?php edit_post_link('Edit', '', ' | '); ?> <?php the_time('d F Y') ?> | Posted By: <?php the_author_posts_link('namefl'); ?> | <?php the_category(', ') ?> | <?php comments_popup_link('No Comment', '1 Comment', '% Comments'); ?> | <a href="<?php the_permalink() ?>" rel="bookmark" title="Permanent Link to <?php the_title(); ?>"  class="more">Read More</a></div>

		<br><br>

</div>

	<div class="alt"><span></span></div></div>

		<?php endwhile; ?>

		<div id="navigation">

			<div class="alignleft"><?php next_posts_link('<strong>Older Entries</strong>') ?></div>

			<div class="alignright"><?php previous_posts_link('<strong>Newer Entries</strong>') ?></div>

		</div>

	<?php else : ?>

		<div class="kutu">

	<div class="ust"><span></span></div>

		<h2 class="center">Not Found</h2>

		<p class="center">Sorry, but you are looking for something that isn't here.</p>

		<?php include (TEMPLATEPATH . "/searchform.php"); ?>

	<div class="alt"><span></span></div></div>

	<?php endif; ?>

	</div>

	</div>

<?php get_sidebar(); ?>

<?php get_footer(); ?>