When I mark a few messages in my INBOX (witg Ctrl+Left mouse click) an then drag them into another folder it does not work. I get the "Move/Copy/Cancel" dialog as expected, but when I select "Move", nothing seems to happen - I still can see and access those messages in the source folder. When I look into the destination folder, I can find those messages there, too. When I restart kmail/kontact, the messages are no longer visible in the source folder - so the mails have actually been moved correctly. So the underlying mechanism seems to work, the mails are just not removed from the item view.
*** This bug has been marked as a duplicate of bug 380182 ***