wxGrid: Problem with unicode mathematical symbols

[Massi]

Hi everyone, I'm trying to build (on windows environment) a grid in
which every cell contains a mathematical formula, the problem is the
following:
when I try to put in the cells some mathematical symbol (such as those
for "belong to", "for all" or "exists") with the method SetCellValue I
always see "∊" as the value of the cells, even if I use both the
unicode wx version and the right unicode strings for the symbols (such
as u'\u2208' for "belong to" ). In fact if I do (on IDLE):

print u'\u2208'

everything works fine. I can't understand why I am wrong. I also tried
to change the font of the cells in "Arial Unicode MS", but the result
was the same.
Have you got any idea about?. Thanks in advance,
Massi