5.3.0 beta build from source fails on OSX 10.6 with Xcode 4.2

/Developer/usr/bin/clang++ -c -Xclang -include-pch -Xclang .pch/debug/QtGui_debug/c++.pch -pipe -g -isysroot /Developer/SDKs/MacOSX10.6.sdk -mmacosx-version-min=10.6 -fvisibility=hidden -fvisibility-inlines-hidden -fno-exceptions -Wall -W -fPIC -DQT_NO_MTDEV -DQT_NO_LIBUDEV -DQT_NO_EVDEV -DQT_NO_USING_NAMESPACE -DQT_BUILD_GUI_LIB -DQT_BUILDING_QT -DQT_NO_CAST_TO_ASCII -DQT_ASCII_CAST_WARNINGS -DQT_MOC_COMPAT -DQT_USE_QSTRINGBUILDER -DQT_DEPRECATED_WARNINGS -DQT_DISABLE_DEPRECATED_BEFORE=0x050000 -DQT_USE_BUNDLED_LIBPNG -DQT_NO_EXCEPTIONS -D_LARGEFILE64_SOURCE -D_LARGEFILE_SOURCE -DQT_CORE_LIB -I../../mkspecs/macx-clang -I. -I../../include -I../../include/QtGui -I../../include/QtGui/5.3.0 -I../../include/QtGui/5.3.0/QtGui -Iimage -I../3rdparty/libpng -I/Developer/SDKs/MacOSX10.6.sdk/System/Library/Frameworks/OpenGL.framework/Versions/A/Headers -I/Developer/SDKs/MacOSX10.6.sdk/System/Library/Frameworks/AGL.framework/Headers -I../../lib/QtCore.framework/Versions/5/Headers -I../../lib/QtCore.framework/Versions/5/Headers/5.3.0 -I../../lib/QtCore.framework/Versions/5/Headers/5.3.0/QtCore -I.moc/debug -F/Users/giorgio/Developer/qt-everywhere-opensource-src-5.3.0-beta/qtbase/lib -o .obj/debug/qopenglfunctions.o opengl/qopenglfunctions.cpp
opengl/qopenglfunctions.cpp:3324:20: error: assigning to 'void (*)(GLenum, GLint, GLint, GLsizei, GLsizei, GLint, GLenum, GLenum, const GLvoid *)'
      from incompatible type 'void (GLenum, GLint, GLenum, GLsizei, GLsizei, GLint, GLenum, GLenum, const GLvoid *)'
        TexImage2D = ::glTexImage2D;
                   ^ ~~~~~~~~~~~~~~
1 error generated.
make[4]: *** [.obj/debug/qopenglfunctions.o] Error 1
make[3]: *** [debug-all] Error 2
make[2]: *** [sub-gui-make_first] Error 2
make[1]: *** [sub-src-make_first] Error 2
make: *** [module-qtbase-make_first] Error 2