how to rebuild vlc for android

[busybeeCS]

i've successfully built vlc libraries, to make some changes to ffmpeg or avconv module, i enter ./vlc/contrib/contrib-android-arm-linux-androideabi/ffmpeg directory and remake it like this:
make clean
make
then i come back and do sh compile.sh,. what a pity, i cannot see any changes of the ffmpeg modules, am i wrong?
can anybody tell me how to rebuild vlc after we do some changes to some particular module?

[edwardw]

Did you make the changes in an active section of the Makefile? Some parts of Makefiles are conditionally disabled.