Ugh, when did that "forum rule" crop up? Irritating. Anyway you will be able to define a function which will add the date, but only to posts not pages:
function my_create_output_date ($html, $class, $pic, $attr) {
if (is_object($pic['page'])) {
if ($pic['page']->post_type == 'post' && strlen($pic['page']->post_date)) {
$html .= '<p class="' . $class . '-date">' . mysql2date('j M Y', $pic['page']->post_date) . "</p>\n";
}
}
return $html;
}
and then add it into the filter list after the image and the title but before the excerpt:
add_filter('autonav_create_table_item', 'my_create_output_date', 18, 4);