Howto disable a menu item

[Sameer Rahmani]

Hi,
according to this:
http://www.gnu.org/s/emacs/manual/html_node/elisp/Simple-Menu-Items.html

by setting the real binding of a menu item we can disable that i tried
all the methods that above link provided for disabling a menu item but
none of them works and i wonder why? is there any changes in those
commands?

I'm using Emacs 23.2