I downloaded QtCreator 2.0 and tried to compile:

Output:

C:\Users\Sasa\Downloads\qt-creator-2.0.0-src\build>mingw32-make
cd src/ && mingw32-make -f Makefile
mingw32-make[1]: Entering directory `c:/Users/Sasa/Downloads/qt-creator-2.0.0-src/build/src'
cd libs/ && c:/Qt/2010.04/mingw/bin/mingw32-make -f Makefile
mingw32-make[2]: Entering directory `c:/Users/Sasa/Downloads/qt-creator-2.0.0-src/build/src/libs'
cd qtconcurrent/ && c:/Qt/2010.04/mingw/bin/mingw32-make -f Makefile
/usr/bin/sh: c:/Qt/2010.04/mingw/bin/mingw32-make: Invalid argument
mingw32-make[2]: *** [sub-qtconcurrent-make_default-ordered] Error 126
mingw32-make[2]: Leaving directory `c:/Users/Sasa/Downloads/qt-creator-2.0.0-src/build/src/libs'
mingw32-make[1]: *** [sub-libs-make_default-ordered] Error 2
mingw32-make[1]: Leaving directory `c:/Users/Sasa/Downloads/qt-creator-2.0.0-src/build/src'
mingw32-make: *** [sub-src-make_default-ordered] Error 2

I tried entering in subdirectories (./src/libs) and then running mingw32-make, which worked fine, except for 3rdparty. Then I have to enter 3rdparty and invoke again mingw32-make, and that worked too.