I'm while using following .htaccess with Wordpress to get rid of index.php in the visible URL. This works but forces an http redirect therefore the URL alterations in the browser window. Basically take away the [R] it no more works. Why would this happen?

RewriteEngine On
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.*)$ /index.php/$1 [R]