Matrox drivers and Trolltech's Qt

I have for some time been developing applications using Trolltech's Qt.
Recently I installed a Matrox Millennium P650 card and started to get odd
behaviour when Dialog windows were first displayed. With Qt3 applications
the effect was to cause the dialog window to display at a larger size than
expected when displayed for the first time and then revert to normal
behaviour after resizing. Moving on to the more recent Qt4 release the
affect was more obvious; when previewing a new dialog in Qt's Designer app
the dialog loses its title bar and frame and gets placed in the top-left
corner of the screen. There was no such problems with Microsoft
apllications or indeed any other than Qt applications.

The driver for the Matrox graphics card (millennium P650) I am using
provides the option (in their words): 'save and restore the size and
position of program windows each time you open and close program windows'
and in my case this option was turned on; turning it off solves the problem.

Clearly, the Matrox driver must be up to tricks with the Win32 api and Qt is
following a different practice in its window creation from that used in
other applications. The simple solution for the developer is to turn the
option off.

I should perhaps mention that the problem was still present using the latest
Matrox driver P650 1.11.0.114 and Qt4.1.4.

I hope this will be of some interest to any Qt developers out there.

Mike