configure fails to create QtCore/qconfig.h

I'm trying to compile the new Qt 5.1.0 release with my usual configure and MinGW but it raise an error as soon as I start mingw32-make saying that qconfig.h doesn't exist. It is not located in the sources I downloaded from Qt-project but it is included in qglobal.h

Configure arguments :
-opensource -confirm-license -nomake demos -nomake examples -platform win32-g++ -icu -openssl -qt-libjpeg -qt-libpng -qt-zlib -I C:\openssl-1.0.1e\include -L C:\openssl-1.0.1e -I C:\icu\include -L C:\icu\lib

C:\Qt\Qt5.1.0\src\qtbase\include/QtCore/../../src/corelib/global/qglobal.h:59:28
: fatal error: QtCore/qconfig.h: No such file or directory