I use two or more keyboard layouts. I often use CTRL-. and CTRL-, to move between tabs. The thing is that I think that konqueror is using the first layout, ie the one highest in "Keyboard layout".
/ and ' is also following the same pattern. They are only triggered on "highest" keyboard layout keys.

I do think this is a bug but I would really like to see if someone else has experiensed this before I submit one.

I use KDE 4.4.5 with kubuntu lucid packages.