netjukebox

Hi!
I'm trying to login to my site (installed in a subfolder: /jukebox) and the following message appears:
Warning: require_once(/home/www/MySite.se/jukebox/include/config.inc.php) [function.require-once]: failed to open stream: No such file or directory in /home/www/MySite.se/jukebox/include/initialize.inc.php on line 65

My question is: do I have to install in the root of my domain?
If not, can I change PHP code for home directory, (and how), to remedy the above warning.

PS. My domains are located under /home/www like this:
/home/www/MySite.se
/home/www/MySite.dk
and so on.

PPS. Here is the code from initialize.inc.php:
// +------------------------------------------------------------------------+
// | Get home directory |
// +------------------------------------------------------------------------+
$directory = dirname(__FILE__);
$directory = realpath($directory . '/..');
$cfg['home_dir'] = str_replace('\\', '/', $directory) . '/';

reszel wrote: My question is: do I have to install in the root of my domain?

No

Does the following file (case sensitive on linux) exist?

Yes, it does. Sorry I forget to tell you that the second ERROR message looks like this:
Fatal error: require_once() [function.require]: Failed opening required '/home/www/MySite.se/jukebox/include/config.inc.php' (include_path='.:/usr/share/php:/usr/share/pear') in /home/www/MySite.se/jukebox/include/initialize.inc.php on line 65
PS. MySite is a dummy for my real site.

phpinfo on this server is here: http://www.onkologen.dk/phpinfo.php
and it's the latest version of netJukebox:
$cfg['netjukebox_version'] = '5.07f';

Very strange! My site is up an running!(http://zxc.se/jukebox/) Maybe there was a problem with my hosting?
Sorry for taking your time