I've noticed that in Kontact, I'm unable to drag and drop email addresses from headers to my Contacts button, which I recall using to easily add a new entry to my address book, and dragging a entry in the address book to the Mail icon, to start composing a new message with that field pre-populated.
This was working in kde3.5, and on Kontact on Beta1 (i had gotten my contacts imported though that method before the switch to Beta2, so I didn't need to worry about it.) I can, however, drag and drop into the calendar, Todo List, and Popup Notes sections, so it doesn't appear to be an issue with the drag and drop functionality.
I've also tested this on a fresh install of 2010 (in a VM of course), and still no drag and drop, so I can say that it's not due to an error in a configuration file.
The documentation for Kontact pretty much promotes this ability, as does their website. So, my query is:
Is this a bug from the latest version of Kontact/Kmail/Kaddressbook in repos, or is there a hidden configuration somewhere I can tweak to enable this?