This patch fixes the bug: Viewer/editor unused submenu Game - ID: 2981303
(There were other unused toplevel menu entries as well, the patch fixes them all.)
fix bogus toplevel entries being shown in the viewer menu
Another patch for the same issue was been posted one month ago at: http://groups.google.com/group/krusader-devel/t/283cde99dd67ab68
I think my solution is the right one: it also fixes the warnings about krviewer.rc not being found and it lets the bogus menus not be created in the first place (by providing an empty menu bar for the KParts to merge their menus into) rather than just hiding them like the other patch does.
I already applied the other patch, but i will look into it again.