-Please check that gtk-config is in path, the directory
-where GTK+ libraries are installed (returned by
-'gtk-config --libs' command) is in LD_LIBRARY_PATH or
-equivalent variable and GTK+ is version 1.2.3 or above.
+The development files for GTK+ were not found. For GTK+ 2, please
+ensure that pkg-config is in the path and that gtk+-2.0.pc is
+installed. For GTK+ 1.2 please check that gtk-config is in the path,
+and that the version is 1.2.3 or above. Also check that the
+libraries returned by 'pkg-config gtk+-2.0 --libs' or 'gtk-config
+--libs' are in the LD_LIBRARY_PATH or equivalent.