Email with Postfix

edit

Hello,
I m running Askbot on CentOS with apache and mod_wsgi.
Its running almost perfectly fine right now but the emails wont work...
I have postfix installed which is also used by an PHP application on the same server and is working.
But I dont know how to configure Askbot properly to use it.
Right now I m using this configuration in the settings.py:

SERVER_EMAIL         = 'my@e.mail.com'
DEFAULT_FROM_EMAIL   = 'my@e.mail.com'
EMAIL_HOST_USER      = ''
EMAIL_HOST_PASSWORD  = ''
EMAIL_SUBJECT_PREFIX = '[MySite Askbot]'
EMAIL_HOST           = '127.0.0.1'
EMAIL_PORT           = '25'
EMAIL_USE_TLS        = FALSE
EMAIL_BACKEND        = 'django.core.mail.backends.smtp.EmailBackend'

Does anyone know why its not working and how to make it work?

Greetings
Hering

Edit: I'm also using SELinux on this server