Must have the xserver-fbdev package installed, then copy the file /usr/share/doc/xserver-fbdev/examples/XF86Config.fbdev to /etc/X11/XF86Config, then edit this file to reflect the color depth you've chosen from the "vga=foo" stanza in /etc/lilo.conf (with vga=791 it's 16 bits (the resolution is 1024x768, but that's irrelevant here)) and also edit the mouse information to reflect the correct protocol and device (in my case, device is /dev/gpmdata and the protocol is Microsoft).
[ninja edit: forgot a step HERE]
Now you have to edit /etc/X11/Xserver and replace the first line with the path to your FBDev X server; for me it's "/usr/bin/X11/XF86_FBDev".
Now you should have functioning X.
The above works for VMware Player 4.x on Windows 7 and may work on other platforms.
I'd forgotten how /ugly/ old versions of Window Maker are.
 See here for a table of framebuffer resolutions & color depths:http://www.pendrivelinux.com/vga-boot-m ... esolution/