widgets are not aligned well inside a QMainWIndow or QDialog

There seems to be some issues since QT4.6.2 release where the widgets don't align well in QMainWindow and QDialog, seems like the spacing is lost. Ive attached an example program to show this issue and instructions below to reproduce.
The alignments were fine in PR1.1 , it has changed in PR1.2
Ive also provided links to some screenshots to explain the issue well.

STEPS:
=======
Compile the example with qmake from /opt/qt4-maemo5/bin which is QT4.6 in PR1.1 and run on the device with QT4.6 libs from PR1.1 installed in /opt/qt4-maemo5/lib
~$: ldd TEMP2
....
libQtGui.so.4 => /opt/qt4-maemo5/lib/libQtGui.so.4 (0x40142000)
libQtCore.so.4 => /opt/qt4-maemo5/lib/libQtCore.so.4 (0x40bfd000)
....

and this is the result
http://bit.ly/bH2ApK

Then
Compile the example with qmake from /usr/bin which is QT4.6 in PR1.2 and run on the device with QT4.6 libs from PR1.2 installed in /usr/lib
~$: ldd TEMP2
....
libQtGui.so.4 => /usr/lib/libQtGui.so.4 (0x40139000)
libQtCore.so.4 => /usr/lib/libQtCore.so.4 (0x40bf4000)
....

and you will see this
http://bit.ly/bIpRi0

I think some default alignments may have been changed in the styles.

Thanks again for taking a look.