[Qt-creator] doubt about defines

[Linos]

Hi,
	i am trying to use QtCreator to edit a project that uses autoconf, the
resulting config.h in my machine have this line:

#define HAVE_LIBAVCODEC 1

and Qt creator disables the code portions that are in a ifdef like this if the
file don't include explicitly  config.h:

#if HAVE_LIBAVCODEC
..disabled code in grey

I have tried copying config.h in a .config file in the project directory but
still i have the same result, what i am missing? how could i enable this code
portions other than change all the files to include config.h? Thanks!

Regards,
Miguel Angel.