If you see a load of compile errors from Qt4 classes when doing a compile, this is sometimes caused by your #include statements.
To fix it, replace all the #include <qwhatever>with a single
#include <QtGui>
instead. (For GUI elements anyway. See /usr/include/qt4/Qt directory for other default includes like QtNetwork etc etc)
You should be using that anyway, but QT3 habits die hard.
