to Thread of Not to Thread messages... a problem

[Richard]

there seems to be a glitch with kmail of Not opening JUST new added thread messages,
instead all threads get open, Even thou I have selected open thread that contain new message.
under list options.

All threads are still open, even when I closed them all
in all folders, is there a way to fix this ?

Other words, if I open a folder, I should only see a thread open that contain a new message.

TIA

Richard