When wxWidgets is compiled as DLL,and wxFreeChart is embedded (/D_LOCAL_) in another project, there are many linkage errors.
The errors are very easily solved by replacing the declarations "WX_DECLARE_EXPORTED_OBJARRAY" with "WX_DECLARE_USER_EXPORTED_OBJARRAY", so the WXDLLIMPEXP_CORE is replaced by WXDLLIMPEXP_FREECHART.
I attach the small patch to fix this. Please, apply it to trunk. I tried myself just in case, but obviously had no rights...