If I compile the following with TeX:
\special{ps: 1 1 0 0 setcmykcolor} Hello there \end
xdvi displays the text in yellow, whereas it ought to be blue. It appears the colour is being interpreted as RGB rather than CMYK.
Incidentally, xdvi -nocolor -noghostscript doesn't succeed in turning off the colour, and xdvi -rv doesn't reverse the colour.
$ xdvi -version
xdvik version 22.84.16 (Xaw toolkit)
Libraries: kpathsea version 6.0.0, T1lib version 5.1.2