OpenGL ES Cursor Artefacts

ieatlint

I'm having an odd artefact issue with OpenGL ES.

Quick platform notes:

OMAP3 system with a PowerVR 530
Running X
Problem has appeared in Qt4.7.4 and Qt4.8
Only tested with QML via qmlviewer and a similar QDeclarativeView based app

When an element is initiall drawn on the screen, if the mouse cursor is over it, an artefact consisting of a black rectangle will be left. If the element is forced to be redrawn (such as by moving it or other), the artefact disappears. The cursor doesn't cause this issue except when an element is drawn for the first time.

A really uninteresting example image of the issue:
http://i.imgur.com/FMbsV.jpg
(This is just a basic QML Rectange element)

So far I've confirmed beyond all doubt that setViewportUpdateMode( QGraphicsView::FullViewportUpdate ) is being set on the QDeclarativeView, and that the the graphics driver SDK on my build system is identical to the one on the device.
The problem does not exist at all if OpenGL is not used.

Any help/insight would be greatly appreciated!

Thanks