compiling app with unsigned char breaks wx/mimetype.h in 2.8.0rc1

[Alicia da Conceicao]

Hi everybody:

Up until now, for more than 3 years, with the numerous 2.4.*, 2.5.*, and 2.6.*
releases, on wxMSW, wxWinCE, wxMac, wxGTK, wxX11, and other platforms,
I have always been able to compile all of my personal wx applications using
the unsigned-char option:

        /J     (with VC++)
        -funsigned-char   (with gcc)

But now for some reason, now with the new wxMSW 2.8.0rc1 and VC++ 6.0,
I now get the following error whenever I include <wx/mimetype.h>:

=====================================================
wx/mimetype.h(136) : error C2666: '+' : 5 overloads have similar conversions
=====================================================

Is there any reason why unsigned-char support for user applications was
broken in 2.8.0rc1?  Every other opensource library I have come across
allows user applications to compile with unsigned-char.

Alicia.