What is it your trying to achieve?

URL rewriting is usually used to convert data inputs into a clean url eg
mysite.com/showproduct.php?id=1391
to
mysite.com/showproduct/1391

If that's all you want it can be done by simply changing the .htaccess file with the FilesMatch tag. In the example above add:


<FilesMatch "^showproduct$">
ForceType application/x-httpd-php
</FilesMatch>

then in your code put

$expl = explode("/",$_SERVER["REQUEST_URI"]);
$id = $expl[count($expl)-1];

All this should be enabled by defult!

If your wondering why any .htaccess file seems to disappear once you upload it, that's because any file that begins with . in linux is hidden. Its there, just your ftp client cant see it.