i18n dependant $is_front

I've used the switchtheme module to be able to switch between themes, and every time I switch theme on my front page (www.example.com), I've been transported to www.example.com/en/node.
Since in my page.tpl.php I'm checking the $is_front variable and I'm using for showing my blocks, somehow i18n module just can't work together with this variable.

I've found this post, but it didn't solve my problem: http://drupal.org/node/71721

Variations of a frontpage:
www.example.com
www.example.com/en/
www.example.com/hr/
www.example.com/en/node
www.example.com/hr/node
www.example.com/en/frontpage
www.example.com/hr/frontpage

Is there any clean way to force $is_front to send TRUE in case of all of these URLs mentioned from above?