On symfony is a good idea to use the referer to costomize some messages, like this one below.
in template, you have to make a condition:
<?php if( $sf_request->getReferer() != '' ): ?>
The page <?php echo $sf_request->getParameter('page'); ?> was changed.
<?php else: ?>
The page <?php echo $sf_request->getParameter('page'); ?> not exists, check if you type correctly.
<?php endif; ?>