[support] How to display blocks in frontpage/blog page

Hi, How do I display specific blocks in frontpage and blog page and to do it in reverse also. I tried putting these codes <code> To display in front page: <?php if (drupal_is_front_page()) : ?> </code> <code> To display in reverse: <?php if (!drupal_is_front_page()) : ?> </code> in the "Page specific visibility settings"--->" Show if the following PHP code returns TRUE (PHP-mode, experts only). " but it doesn't work. Your help is highly appreciated. Thank you very much. Regards, Richard R. Cahilig