Comment 51 for bug 338669

Yet more update:

Successfully installed Qt 4.5.1 from https://launchpad.net/~kubuntu-experimental/+archive/ppa/
but still no break through.

At a closer look after all those updates, the issue seems to be reduced:
 + previously kmail was affected (view and composer), looks good now
 + konqueror:
 * scrolling only broken an certain web pages
 * some artifacts disappear after a short delay
 - kate: forward scroll OK, backward scroll fails to repaint: areas remain white.

re konqueror: problems are reproducable mostly on pages that combine fixed
positions with scrollable content. A funny effect is reproducable on this page:
www.opodo.co.uk (no advertizing intended): some part of the form consistently
fails to repaint during scrolling (the part containing line edits).
Also when searching within a page, repaint frequently fails.

My current belief is: this bug is actually a mixture of several bugs, some of which
might have been fixed in Qt 4.5.1 or KDE 4.2.3. Remaining bugs could actually
be bugs of konqueror and kate respectively.