How to add bbdb/gnus-split-method into existing nnmail-split-methods?

How to add bbdb/gnus-split-method into existing nnmail-split-methods?

[Albert Chun-Chieh Huang]

Hello, all,

I've spent a whole day to study how to add bbdb/gnus-split-method into
existing nnmail-split-methods, but I can't solve it by myself. 

Now, I already have a list of nnmail-split-methods, so I don't want to
use nnmail-split-fancy. And I want to split all BBDB members into a
group "mail.private", which means private mails, and all other mails
use the existing nnmail-split-methods. So I add bbdb/gnus-split-method
into the front of nnmail-split-methods, as follows:
(setq nnmail-split-methods
        '(
	  (bbdb/gnus-split-method)
	  ("mail.emacs-devel"
                "^From:.*emacs-devel@gnu.org\\|^To:.*emacs-devel@gnu.org\\|^Cc:.*emacs-devel@gnu.org\\|^List-Id:.*emacs-devel.gnu.org")
          (blah blah blah)))

And this doesn't work, I tried to trace it, but I couldn't find any
solution yet. Any idea? Thanks in advance.
-- 
Chun-Chieh Huang, aka Albert   | E-mail: jjhuang AT cm.nctu.edu.tw
黃俊傑                         |
Department of Computer Science | 
National Tsing Hua University  | MIME/ASCII/PDF/PostScript are welcome!
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