Error htaccess (RewriteEngine )

Hi,
I want redirect www.site.com/user/john =>>
www.site.com/script.php?user=john

My htacces is:
--- .htaccess --
RewriteEngine on
Options +FollowSymlinks

RewriteRule ^user/(.*) script.php?user=$1
--------------

But i have the internal server Error

What 's wrong?

I have tryed also with:
RewriteRule ^user/(.*) script.php?user=$1 [L,R]
or
RewriteRule ^user/(.*) /path/script.php?user=$1

thanks

> "Internal server error" could mean anything. Check your error_log,
> it should give a little more clues, I suspect that this is an
> error from PHP, not from Apache.

It's a Hosting error (Aruba.it ;) )
Now it's ok..
Thanks Davide