[metapost] problem with DVItoMP

[Liunian]

hi all,

    I have more detail about the dvitomp problem.

    I am a Chinese user of metapost. If i only deal with
ascii words, metapost works well. But when it deal with
Chines words (with GBK encoding), some strange thing
happened. metapos can only deal with 3 different chinese words.
for example:
     in the file test.mp fig(1) only contains five same chinese words "one",
 fig(2) contians four different chinese words,"one two three four".
The result is that fig(1) can work well, but fig(2) cannot. 
    

======================test.mp========================
verbatimtex
%&latex
\documentclass{article}
\usepackage{amsmath}
\usepackage{amssymb}
\usepackage{mathcomp}
\usepackage{CJK}
\begin{document}
\begin{CJK*}{GBK}{song}
etex

beginfig(1);

    label.bot(btex 一一一一一一  etex , (2,2));  % work well
endfig;

beginfig(2);

   label.bot(btex 一二三四  etex , (2,2));   % errors occurred  
 
endfig;

verbatimtex
\end{CJK*}
\end{document}
etex
end;
=====================================================