Custom sidebars using pages custom fields

Add a different image to the sidebar on each page using pages custom fields. I have found some PHP code which may be useful but I have been unsuccessful making it work. Here is the code that I have tried to use by placing it in a text box in the sidebar widget: <!-- Sidebar Images --> <div class="side_box" style="display: block"> <?php rewind_posts(); /*enables query data to be passed over again in another loop*/ ?> <?php while (have_posts()) : the_post(); ?> <!-- Do stuff... --> <?php $sidebar_images = get_post_meta($post->ID, 'sidebar-image', false); //get the list of values associated with the key "sidebar-image" if ($sidebar_images){ /*if non-empty list*/ ?> <h3>custom fields:</h3> <ul> <?php foreach($sidebar_images as $sb_image) { echo '<li>'.$sb_image.'</li>'; } ?> </ul> <?php } ?> <?php endwhile; ?>