Compiler can't find header file in Qt5 RC1 MinGW build (but it exists)

[unai_i]

Hello,
I am having a weird situation where my compiler (MinGW gcc 4.7) is not finding a header file but I can find the header file in file system and can even open it by ctrl+click on path from QtCreator. Google doesn't return useful information on this.
The error output is:
@..........\Qt5.0.0rc1\qt-everywhere-opensource-src-5.0.0-rc1\qtbase\include\QtQml/qqmlextensionplugin.h:1:68: fatal error: ../../../qtdeclarative/src/qml/qml/qqmlextensionplugin.h: No such file or directory@

Background: I built Qt5 myself from sources with the same MinGW I am using for my project. I had the same problem with Qt5 beta2 but as I had some issues building it I left it aside. However this time Qt built without interruption but still have the problem.

Any ideas?