The SDK-support on PowerPC Macs is broken, which used to enable builds created on 10.4 to run on 10.3.
Linking VLC with SDK-support fails like this:
g++ -Wsign-compare -Wsign-compare -Wall -I/Users/buildslave/slave/nb-g5-osx-trunk/build/./extras/contrib/include -D_INTL_REDIRECT_MACROS -DMACOSX_DEPLOYMENT_TARGET=10.3 -isysroot /Developer/SDKs/MacOSX10.3.9.sdk -pipe -isysroot /Developer/SDKs/MacOSX10.3.9.sdk -Wl,-syslibroot -Wl,/Developer/SDKs/MacOSX10.3.9.sdk -o vlc vlc-vlc.o -g -framework vecLib /Users/buildslave/slave/nb-g5-osx-trunk/build/./extras/contrib/lib/libintl.dylib -framework vecLib -framework QuickTime -framework Carbon -framework CoreAudio -framework AudioUnit -framework AudioToolbox -framework IOKit -framework Cocoa -framework Carbon -framework QuickTime -ObjC -framework OpenGL -framework AGL -Wl,-bind_at_load -L/Users/buildslave/slave/nb-g5-osx-trunk/build/./extras/contrib/lib src/libvlc.a ./modules/misc/memcpy/libmemcpyaltivec.a ./modules/video_chroma/libi420_yuy2_altivec.a ./modules/demux/liblive555.a ./modules/mux/mpeg/libmux_ts.a ./modules/demux/libmkv.a ./modules/codec/ffmpeg/libffmpeg.a ./modules/stream_out/libstream_out_switcher.a ./modules/codec/libquicktime.a ./modules/codec/libtheora.a ./modules/audio_output/libauhal.a ./modules/gui/macosx/libmacosx.a ./modules/visualization/libgoom.a -L/usr/local/lib -L/Users/buildslave/slave/nb-g5-osx-trunk/build/extras/contrib/lib /Users/buildslave/slave/nb-g5-osx-trunk/build/extras/contrib/lib/libshout.dylib /Users/buildslave/slave/nb-g5-osx-trunk/build/extras/contrib/lib/libvorbis.a /Users/buildslave/slave/nb-g5-osx-trunk/build/extras/contrib/lib/libspeex.dylib -lpthread /usr/lib/libiconv.dylib -lc -L/Users/buildslave/slave/nb-g5-osx-trunk/build/extras/contrib/src/live/UsageEnvironment -lUsageEnvironment -L/Users/buildslave/slave/nb-g5-osx-trunk/build/extras/contrib/src/live/groupsock -lgroupsock -L/Users/buildslave/slave/nb-g5-osx-trunk/build/extras/contrib/src/live/BasicUsageEnvironment -lBasicUsageEnvironment -L/Users/buildslave/slave/nb-g5-osx-trunk/build/extras/contrib/src/live/liveMedia -lliveMedia /Users/buildslave/slave/nb-g5-osx-trunk/build/extras/contrib/lib/libdvbpsi.dylib -lz -lmatroska -lebml -lpostproc -lavformat -lavcodec /Users/buildslave/slave/nb-g5-osx-trunk/build/extras/contrib/lib/libmp3lame.a /Users/buildslave/slave/nb-g5-osx-trunk/build/extras/contrib/lib/libfaac.a -lavutil /Users/buildslave/slave/nb-g5-osx-trunk/build/extras/contrib/lib/libtheora.dylib /Users/buildslave/slave/nb-g5-osx-trunk/build/extras/contrib/lib/libogg.dylib -lobjc -L/Users/buildslave/slave/nb-g5-osx-trunk/build/extras/contrib/src/goom/src/.libs /Users/buildslave/slave/nb-g5-osx-trunk/build/extras/contrib/lib/libgoom2.a -lm
/usr/bin/ld: warning multiple definitions of symbol _locale_charset
/usr/lib/libiconv.dylib(localcharset.o) definition of _locale_charset
/Users/buildslave/slave/nb-g5-osx-trunk/build/./extras/contrib/lib/libintl.dylib(localcharset.o) definition of _locale_charset
/usr/bin/ld: multiple definitions of symbol _localtime_r
/Developer/SDKs/MacOSX10.3.9.sdk/usr/lib/gcc/powerpc-apple-darwin8/4.0.0/../../../libpthread.dylib(localtime.So) definition of _localtime_r
/Users/buildslave/slave/nb-g5-osx-trunk/build/./extras/contrib/lib/libavformat.a(os_support.o) definition of _localtime_r in section (__TEXT,__text)
collect2: ld returned 1 exit status
Additionally, our current SDK-support does only work with Xcode 2.1. The compilation of gettext with Xcode 2.2 or 2.3 fails because GCC isn't found correctly (configure complains that it can't create executables).