########################### Flags #################################
-CFLAGS = @TOOLKIT_DEF@ @WXDEBUG_DEFINE@ @CFLAGS@ $(EXTRADEFS)
+#
+# @CPPFLAGS@ (gnu standard) is not C++ flags, but flags for the "cpp"
+# preprocessor. Unfortunately whoever wrote this now uses CPPFLAGS for
+# C++ like CFLAGS for C. :-(
+# We *must* include @CPPFLAGS@ in both of these, to make sure that all
+# header files get found. (KB)
+
+CFLAGS = @TOOLKIT_DEF@ @WXDEBUG_DEFINE@ @CFLAGS@ @CPPFLAGS@ $(EXTRADEFS)
CPPFLAGS = @TOOLKIT_DEF@ @WXDEBUG_DEFINE@ @CXXFLAGS@ @CPPFLAGS@ $(EXTRADEFS)
PICFLAGS = @PIC_FLAG@
LDFLAGS = @LDFLAGS@