handling of transformationAnchor inside wheelEevent

There's a difference in handling of transformationAnchor==QGraphicsView::AnchorUnderMouse between 4.6.0 and the previous versions.
Whereas 4.5.x honors the current cursorposition, 4.6.0 doesn't anymore. You have to click the left mousebutton to set the position instead of only using the wheel.

QMatrix mm;
mm.setScale( 2,2);
setTransformationAnchor ( QGraphicsView::AnchorUnderMouse );

setMatrix ( mm, false );