nice find. I had the same problem. But the above wasn't working.
I had to use a more difficult way how to obtain current time respecting the WP time zone. I also had to switch the timezone from UTC-5 to "New York", date_default_timezone_set wasn't working with just UTC-5.
$date = mysql2date('U',$date,false);
$tz = get_option('timezone_string');
date_default_timezone_set( $tz );
$datetime = new DateTime( date('Y-m-d H:i:s') );
$offset = $datetime->getOffset();
$time = $datetime->format('U');
$time = (int)$time + (int)$offset;
//echo '<!-- COMMENT: '.$date.' server: '.$time.' -->';
/// End of addition
$editablecomments = get_option('editable-comments');
if($type == 'edit')
$minutes = $editablecomments['minutes'];
if($type == 'delete')
$minutes = $editablecomments['deleteminutes'];
//if($date >= time() - $minutes * 60)
if($date >= $time - $minutes * 60)
Other than that, the "Comment updated" message is not showing up in the Thesis. And it also could be more secure. If you post a comment, everybody from the same IP will be able to edit it, it should probably check the WP commenting cookie at least.