Show commenter IP address to admins (Drupal 7 / AdaptiveTheme)
It looks like you're adding your code within the adaptivetheme_preprocess_node function but you should be working within the adaptivetheme_preprocess_comment function (a little further down the page).

Specifically the following could be modified with your code above as a starting point (starting at line 835 in preprocess.inc for AdaptiveTheme 3.2):

  $vars['submitted'] = t('Submitted by !username on !datetime',
array(
  '!username' =&gt; $vars['author'],
  '!datetime' =&gt; '&lt;time datetime="' . $vars['datetime'] . '" pubdate="pubdate"&gt;' . $vars['created'] . '&lt;/time&gt;',
)
);