There exists a bug in the zbench WordPress theme when used together with qtranslate plugin resulting in a malformed date string in the comments section. Fortunately, there exists a quick fix for this problem.
Simply replace corresponding code with the following in the function mytheme_comment in functions.php:
<?php echo mysql2date('Y/m/d/ H:i', $comment->comment_date);?><?php edit_comment_link(__('[Edit]','zbench'),' ','') ?>
Pay special attention to
<?php echo mysql2date('Y/m/d/ H:i', $comment->comment_date);?>
which replaces
<?php printf(__('%1$s at %2$s', 'zbench'), get_comment_date(), get_comment_time()); ?>
That’s it, enjoy!