Htaccess effecting admin login, not sure why?

[bottyz]

Hi all,


I want to implement a non-www to www script in my htaccess as follows:

RewriteEngine on
RewriteBase /
RewriteCond %{HTTP_HOST} ^mydomain.com [NC]
RewriteRule ^(.*)$ http://www.mydomain.com/$1 [L,R=301] 

If I put that in my htaccess everything works great except my admin login. When I enter the username and password it just reverts back to the same login page.

I've read other posts and checked that both configure.php files have the following:

Admin:

define('HTTP_SERVER', 'http://www.mydomain.com');
define('HTTPS_SERVER', 'https://www.mydomain.com');
define('HTTP_CATALOG_SERVER', 'http://www.mydomain.com');
define('HTTPS_CATALOG_SERVER', 'https://www.mydomain.com'); 

Catalog:

define('HTTP_SERVER', 'http://www.mydomain.com');
define('HTTPS_SERVER', 'https://www.mydomain.com'); 

All with the www. But the problem still exists... Any ideas?