Okay, one simple idea.
So if you have somepage.php only the naked version will index in search engines - that is, any that have a query string like somepage.php?lang=de etc will not index.
If you have a dedicated IP you can also prevent indexing on the IP as such:
PHP:
<?php
$qstring = stripslashes($_SERVER['QUERY_STRING']);
if($qstring == '')$robots = '<meta name="robots" content="index,follow,noarchive" />';
else $robots = '<meta name="robots" content="noindex,nofollow,noarchive" />';
echo $robots;
?>
So if you have somepage.php only the naked version will index in search engines - that is, any that have a query string like somepage.php?lang=de etc will not index.
If you have a dedicated IP you can also prevent indexing on the IP as such:
PHP:
<?php
$httphost = $_SERVER['HTTP_HOST'];
$qstring = stripslashes($_SERVER['QUERY_STRING']);
if($qstring != '' || $httphost == '192.168.1.88')$robots = '<meta name="robots" content="noindex,nofollow,noarchive" />';
else $robots = '<meta name="robots" content="index,follow,noarchive" />';
echo $robots;
?>