French/english site

[mic_comte]

 Hi,
My site is in french and in english. To be able to submit to directories without giving the address mysite.com/fr/index.htm (which can be considered as deep link and then refused), I have put a php script at the root of the site to redirect directly the user, depending on the default language of his browser (see below).

The default language is french, but recently I changed it to english when I submit to english directory (so I can read the meta tags easily). Since then, my english index is better ranked in google than the french one.

Do I risk a penalty from Google who could consider that as spamdexing?

Here is my script:

<?php
if ( isset( $_SERVER["HTTP_ACCEPT_LANGUAGE"] ) )
{
   $lang = getenv('HTTP_ACCEPT_LANGUAGE');
   if ( substr ($lang, 0, 2) == 'en' )
   {
      header("Location: http://www.braquedubourbonnais.info/en/index.htm");
   }
   else
   {
      header("Location: http://www.braquedubourbonnais.info/fr/index.htm");
   }
}
else
{
header("Location: http://www.braquedubourbonnais.info/fr/index.htm");
}
?>

[SensoVision]

I believe that Google have no reason for doing so, since you don't play with content to get better ranking but to improve browsing experience of your visitors by accommodating language to country they are coming from.
If I have similar task I would do it without worries although would probably use mod rewrite function instead of one suggested in PHP. Something like described here: http://www.gerv.net/hacking/language-selection/

BTW I've just check your site and it seems that it's still ranked well(at least to my eye) so time time have proved that using such redirects aren't harmful.