[Mailman-Users] how do I read this?

[Dr. Scott S. Jones]

At the prompt, I notice this:

root at fyrenice:/boot# vim /var/mail/scott
You have new mail in /var/mail/scott

I check that mail file and find the following error message:

Traceback (most recent call last):
  File "/usr/lib/mailman/cron/gate_news", line 43, in ?
    from Mailman import mm_cfg
  File "/var/lib/mailman/Mailman/mm_cfg.py", line 50, in ?
    DEFAULT_URL       = none
NameError: name 'none' is not defined

My Defaults.py shows that for my debian package, I should have 
DEFAULT_URL = none set just that way? Do I need to add "none" somewhere 
to define it?