UrlHelper::encodePath() doesn't support Windows paths

I never used Drupal on windows before but now I just wanted to test my module on clean drupal and found out that I just cant use

drupal_add_js(MY_MODULE_ROOT_REL. '\\js\\somejs.js'); 

// or

drupal_add_js(MY_MODULE_ROOT_REL. '/js/somejs.js');

I defined my custom constants as

/**
 * Define root constant. (An absolute path: /home/var/www/)
 * This is used to prevent using drupal_get_path() cause __DIR__ is much faster and
 * don't use database connection to find out there this module is located.
 * @note requires PHP 5.3+
 */
define('MY_MODULE_ROOT', __DIR__);

/**
 * Relative path to this module (sites/default/....)
 */
define('MY_MODULE_ROOT_REL', str_replace(DRUPAL_ROOT. DIRECTORY_SEPARATOR, '', MY_MODULE_ROOT));

Disclaimer:
I know that Windows is not platform for develop but I think it is not good if Drupal won't work on windows too.
I know about drupal_get_path() but I don't want to use database connection just to find out the path to my module (I use drupal bootstrap_database layer and only include constant.inc files)