spam spltting my sys emails

[Richard Riley <rileyrg@googlemail.com>]

Using this set up

   (setq nnimap-inbox "INBOX")
   (setq nnimap-split-methods 'default)
   (setq nnmail-split-fancy (quote (: spam-split)))
   (setq nnmail-split-methods (quote nnmail-split-fancy))

combined with

,----
| spam-split-group is a variable defined in `spam.el'.
| Its value is "Gnus-Spam"
| 
| Documentation:
| Group name where incoming spam should be put by `spam-split'.
`----

I have a select method for nnml which processes var/spool/mail mbox and
usually used to put them in mail.misc group in the nnml-directory
(~/Mail).

Now its determining that all my sys emails from cron etc are spam and
refiling them to spam-split-group, Gnu-Spam. How to stop that?

My nnml group looks like this after using command line "mail" to send an
email from root to myself:-

,----
| Z      1: Gnus-Spam <-- spam splitting created this
|        0: mail.misc
|        1: sys-mail     ;<--- I created this group manually moving a message
`----

Where Gnus-Spam has been newly created by the spam-splitting I assume.

So how to tell the spam-split assigned to nnmail-split-fancy to ignore
the nnml feed?