The suggestion that comes to mind first is the one you don't want: Don't use Debian Woody.
Have you considered upgrading to a newer kernel and installing a different distro? Mandrake 10.1 is quite nice, a free download, and it comes with tons of window managers and you can install them all and freely switch between them without installing and uninstalling software.
My question to you is why would you inflict windowmaker upon yourself? What a horrible desktop that is.
Sorry - I know this isn't the *real* answer and that someone else will answer you with the actual instructions on how to do what you are looking for after I post this, and that you might sneer, but that's what I suggest.