Add custom sidebars to a wordpress thematic theme.js

<?php

register_sidebar(array('name' => 'Home',    'before_title' => '<h3 class="widgettitle">', 'after_title' => '</h3>'));
register_sidebar(array('name' => 'Contact', 'before_title' => '<h3 class="widgettitle">', 'after_title' => '</h3>'));
register_sidebar(array('name' => 'Page',    'before_title' => '<h3 class="widgettitle">', 'after_title' => '</h3>'));
register_sidebar(array('name' => 'Post',    'before_title' => '<h3 class="widgettitle">', 'after_title' => '</h3>'));

function is_contact() {
  return in_array('is_contact', get_post_custom_keys());
}

function sidebar_widgets() {
  echo '<div class="aside main-aside"><ul class="xoxo">';
  if (is_front_page())    { dynamic_sidebar('Home');
  } elseif (is_contact()) { dynamic_sidebar('Contact');
  } elseif (is_page())    { dynamic_sidebar('Page');
  } else                  { dynamic_sidebar('Post'); }
  echo '</ul></div>';
}
add_action('thematic_abovemainasides', 'sidebar_widgets');

?>