Emacs has an extra specifier to defface, min-colors, which allows you to use 
different settings based on the number of colors that can be displayed on a device. 
http://www.gnu.org/software/emacs/elisp/html_node/Defining-Faces.html

It has been showing up in customize-based themes, so I thought I'd make 
them load in XEmacs as well.  An example theme is at
http://git.savannah.gnu.org/cgit/emacs.git/tree/etc/themes/tango-theme.el

--
Jeff Sparkes
jsparkes@gmail.com