Apache/Django subdomains problem

Question

Now I have apache configuration which works only with localhost domain (http://localhost/).

Alias /media/ "/ścieżka/do/instalacji/django/contrib/admin/media/"
Alias /site_media/ "/ścieżka/do/plikow/site_media/"
<Location "/">
    SetHandler python-program
    PythonHandler django.core.handlers.modpython
    SetEnv DJANGO_SETTINGS_MODULE settings
    PythonPath "['/thomas/django_projects/project'] + sys.path"
    PythonDebug On
</Location>
<Location "/site_media">
SetHandler none
</Location>

How can I make it working for some subdomains like pl.localhost or uk.localhost? This subdomains should display the same page what domain (localhost).

Second question: It is possible change default localhost address (http://localhost/) to (http://localhost.com/) or (http://www.localhost.com/) or something else?