Error in menu-bar-update-hook: (wrong-type-argument integer-or-marker-p nil)

[zh.zsl <zh.zsl@xxxxxx>]

This bug report will be sent to the emacs-w3m development team,
 not to your local site managers!!
Please write in simple English, because the emacs-w3m developers
aren't good at English reading. ;-)

Please describe as succinctly as possible:
	- What happened.
	- What you thought should have happened.
	- Precisely what you were doing at the time.

Please also include any Lisp back-traces that you may have.
================================================================
Dear Bug Team!

I use emacs and w3m in winxp, recently, I had updated w3m from CVS
,when I load w3m-mode, can't open bookmarks and session, the message
is " Error in menu-bar-update-hook: (wrong-type-argument
integer-or-marker-p nil)", 

I test it when use "emacs -q", the w3m-mode give the same message.

Sorry, My english is poor! hope you could understand my meaning.
================================================================

System Info to help track down your bug:
---------------------------------------
emacs-w3m-version
 => "1.4.507"
emacs-version
 => "GNU Emacs 23.2.50.1 (i386-mingw-nt5.1.2600)\n of 2010-05-12 on SHAN-PC"
mule-version
 => "6.0 (HANACHIRUSATO)"
system-type
 => windows-nt
(featurep 'gtk)
 => nil
w3m-version
 => "w3m/0.5.1"
w3m-type
 => w3m-m17n
w3m-compile-options
 => ("lang=en" "m17n" "image" "color" "ansi-color" "mouse" "menu" "cookie" "ssl" "ssl-verify" "external-uri-loader" "w3mmailer" "nntp" "alarm" "mark")
w3m-language
 => nil
w3m-command-arguments
 => ("-cookie" "-F")
w3m-command-arguments-alist
 => nil
w3m-command-environment
 => (("CYGWIN" . "binmode"))
w3m-input-coding-system
 => utf-8
w3m-output-coding-system
 => utf-8
w3m-use-mule-ucs
 => nil