The kdeartwork-3.2.1-1 build requires Qt 3.3.1 to allow KDE to use the Plastik theme (and all the other not-built-in themes).
kdeartwork depends on kdelibs, but, from my experience, KDE 3.2.1 works fine without Qt 3.3.1 (with 3.3.0, in my case).
So, I can't actually say kdelibs should depend on Qt 3.3.1. I see it more like kdeartworks should depend on Qt 3.3.1, even though it does not look right. (There might be other packs compiled against 3.3.1 though)
The KDE Requirement list (http://www.kde.org/info/requirements/3.2.php) says that KDE Requires Qt >=3.2.3. In my opinion, all the KDE packs should be built against the same Qt lib, and that lib should be set as a dependency for kdelibs.
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