procmail/gnus problem?

[Nick Papadonis <nick@sturgeon.coelacanth.com>]

Hi.  

I have HOURS trying to find a solution to this problem. I don't know if anyone can point me in the right direction. 

Recently I set up procmail, and attempted to change the gnus startup file to import my procmail directory.  I added the following:
(setq
 gnus-secondary-select-methods '((nnml ""))
 nnmail-spool-file 'procmail
 nnmail-procmail-directory "~/incoming/"
 nnmail-delete-incoming t
)

My mailing lists are spooled into ~/incoming/ and have extensions like 'list.gnus.spool'.
I thought they would be imported to -> list.gnus, etc...

When starting gnus 5.8.8 I get the following error:
Wrong type argument: listp, procmail

I am using xemacs 21.1.12.

Any insight into this error appreciated.  I saw something in the list where nnmail-spool-file shouldn't be set to procmail, but wasn't sure if thats what I wanted.

Thanks.

- Nick

Here is a backtrace.

Backtrace:
Signaling: (wrong-type-argument listp procmail)
  nnmail-get-new-mail(nnml nnml-save-nov "~/Mail/" nil)
  nnml-request-scan(nil "")
  gnus-request-scan(nil (nnml ""))
  gnus-read-active-file-1((nnml "") nil)
  gnus-read-active-file(nil nil)
  gnus-setup-news(nil nil nil)
  byte-code("..." [dont-connect did-connect gnus-group-quit gnus-run-hooks gnus-startup-hook gnus-make-newsrc-file gnus-startup-file gnus-current-startup-file gnus-slave gnus-use-dribble-file gnus-dribble-read-file gnus-use-grouplens bbb-login add-hook gnus-summary-mode-hook gnus-grouplens-mode gnus-setup-news nil level gnus-setup-news-hook gnus-start-draft-setup gnus-group-list-groups gnus-group-first-unread-group gnus-configure-windows group gnus-group-set-mode-line gnus-started-hook] 4)
  gnus-1(nil nil nil)
  gnus(nil)
  call-interactively(gnus)
  command-execute(gnus t)
  execute-extended-command(nil)
  call-interactively(execute-extended-command)