+// notice that even though for many compilers the friend declarations above are
+// enough, from the point of view of C++ standard we must have the declarations
+// here as friend ones are not injected in the enclosing namespace and without
+// them the code fails to compile with conforming compilers such as xlC or g++4
+wxString WXDLLIMPEXP_BASE operator+(const wxString& string1, const wxString& string2);
+wxString WXDLLIMPEXP_BASE operator+(const wxString& string, wxChar ch);
+wxString WXDLLIMPEXP_BASE operator+(wxChar ch, const wxString& string);
+wxString WXDLLIMPEXP_BASE operator+(const wxString& string, const wxChar *psz);
+wxString WXDLLIMPEXP_BASE operator+(const wxChar *psz, const wxString& string);
+
+