hi,
I found the error by my self.
When I create the new wxWidgets-2.8.4 with the UNICODE option in line
mingw32-make -f makefile.gcc USE_XRC=1 SHARED=1 MONOLITHIC=1 BUILD=release UNICODE=1
I forget to add in project -> Build options->#defines tha flag
wxUSE_UNICODE. I put this entry in case could be usefull for guys with the same problem.
Joss.
P.S : The new compiler mingw4.2.1 dw2 seems to be better then th 3.4.5 version. I also hope the guys of wxWidgets remove those warnings about wxWidgets when compiling.
Also let me say that is very hard to find this kind of error just reading the type and the string error produced by the compiler.