Installing xcursor-themes (and selecting core.theme) straightens things out: Now, selecting the default cursor theme (called "KDE classic" !) indeed gives the standard X-cursor theme (or whatever is chosen in /etc/alternatives/x- cursor-theme). So is this a KDE bug or a bug in the debian implementation of KDE? A possible solution to the present reported bug would be to make kdebase- workspace-data depend on xcursor-themes; this is probably better than transforming the oxygencursors dependence into a suggestion...
