Fontconfig - Aug 2012 - how to read config file from current dir (relative to a binary using the lib)

Hello,

How can I make fontconfig look for the config files in the local directory?

Here is the background:

I''m compiling a static ffmpeg binary with libass and fontconfig.
Now ffmpeg (or actually the library which was statically linked to ffmpeg) is
looking for the configuration files in a directory which does not exist on
other systems.
I need to have the library looking for the config files relative to the static
binary.

e.g.:

binary:
	/path/to/binary/my_static_binary
config files:
	/path/to/binary/conf.d
	/path/to/binary/fonts.conf
or
	/path/to/binary/cfg/conf.d
	/path/to/binary/cfg/fonts.conf

Any ideas how I can do this?

Would --sysconfdir=. do this? Is this valid?

Cheers,
  Helmut