Open CV 1.1pre1 MINGW 5.1.6 (GCC 3.4.5) Compile

ren bin bin_original // back up original files
ren lib lib_original // back up original files
cd _make
mingw32-make -f make_all_gnu.mak // for release version
set DEBUG=1
mingw32-make -f make_all_gnu.mak // for debug version