den som virker: 
define('SM_PATH','/');

/* SquirrelMail required files. */
require_once(SM_PATH . 'functions/global.php');
require_once(SM_PATH . 'functions/strings.php');
require_once(SM_PATH . 'config/config.php');
require_once(SM_PATH . 'functions/i18n.php');
require_once(SM_PATH . 'functions/plugin.php');
require_once(SM_PATH . 'functions/constants.php');
require_once(SM_PATH . 'functions/page_header.php');
require_once(SM_PATH . 'functions/html.php');
require_once(SM_PATH . 'functions/forms.php');

-------------------------------------------------------------------

den som ikke virker:

define('SM_PATH','/');

/* SquirrelMail required files. */
require_once(SM_PATH . 'squirrelmail/functions/global.php');
require_once(SM_PATH . 'squirrelmail/functions/strings.php');
require_once(SM_PATH . 'squirrelmail/config/config.php');
require_once(SM_PATH . 'squirrelmail/functions/i18n.php');
require_once(SM_PATH . 'squirrelmail/functions/plugin.php');
require_once(SM_PATH . 'squirrelmail/functions/constants.php');
require_once(SM_PATH . 'squirrelmail/functions/page_header.php');
require_once(SM_PATH . 'squirrelmail/functions/html.php');
require_once(SM_PATH . 'squirrelmail/functions/forms.php');