It turns out not to be a bug in KDE-apps.
I checked the keyboard preferences in Gnome, and the only layout that shows up there is a US-English standard. (It is not marked as standard however)
There should have been a swedish layout, marked as standard. When I added this layout the KDE applications had no problems with the öäå characters.
It seems like the nvidia-config application removed the keyboard-layout options from xorg.conf at some stage. (Or just missed writing them..)
It turns out not to be a bug in KDE-apps.
I checked the keyboard preferences in Gnome, and the only layout that shows up there is a US-English standard. (It is not marked as standard however)
There should have been a swedish layout, marked as standard. When I added this layout the KDE applications had no problems with the öäå characters.
It seems like the nvidia-config application removed the keyboard-layout options from xorg.conf at some stage. (Or just missed writing them..)