Subject line says it all.
 
`i' in the Elisp manual, then type `:visible' - nothing.
Type `visible' - no entries for the menu keyword.
 

In GNU Emacs 24.0.50.1 (i386-mingw-nt5.1.2600)
 of 2010-06-28 on 3249CTO
Windowing system distributor `Microsoft Corp.', version 5.1.2600
configured using `configure --with-gcc (4.4) --no-opt --cflags -Ic:/xpm/include'