I tried to comile simple example application:
@
#include <QApplication>
#include <QLabel>

int main(int argc, char *argv[])
{
QApplication app(argc,argv);
QLabel *label = new QLabel("Hello Qt!");
label->show();
return app.exec();
}
@

I did "qmake -project", and "qmake hello.pro", and then I typed "make".
And that gives me error:
"hello.cpp:1:24: fatal error: QApplication: No such file or directory
compilation terminated."

The problem seems to be in qmake. When I make project with QtCreator it's Makefile has different INCPATH variable, and this phase goes without problem (there are other problems but it's another question).
This is INCPATH variable in Makefile created through QtCreator:

"INCPATH = -I/opt/Qt5.1.0/5.1.0/gcc/mkspecs/linux-g++ -I../helloQtCreator -I/opt/Qt5.1.0/5.1.0/gcc/include -I/opt/Qt5.1.0/5.1.0/gcc/include/QtWidgets -I/opt/Qt5.1.0/5.1.0/gcc/include/QtGui -I/opt/Qt5.1.0/5.1.0/gcc/include/QtCore -I. -I. -I."

And this one is created by qmake through terminal:

"INCPATH = -I/opt/Qt5.1.0/5.1.0/gcc/mkspecs/linux-g++ -I. -I. -I/opt/Qt5.1.0/5.1.0/gcc/include -I/opt/Qt5.1.0/5.1.0/gcc/include/QtGui -I/opt/Qt5.1.0/5.1.0/gcc/include/QtCore -I."

Project names are different but why qmake doesn't include
"-I/opt/Qt5.1.0/5.1.0/gcc/include/QtWidgets"
when started manualy from terminal?
And how can I fix it?

Thank you.