Version:            (using KDE 4.2.4)
Installed from:    Gentoo Packages

I often miss addresses in kmails autocompletion; I have no perfect addressbook (who has?), but I just had the idea that kmail could use my inbox + sent folders as additional data sources for possible addresses.

That is - I have a very large (IMAP) folder structure, so in order to let this be efficient, I explicitly propose to only use the main inbox (where spam mails etc. will be deleted / moved from), and the sent-mail folder (which might contain mails sent from other computers, but really indicates that these might be possible future targets as well).

Additionally, it most likely makes sense to use only mails from the last N days, where N might be something between 15 and 200 or so.  (My inbox contains some thousand mails from the last years, which might again be too much otherwise?)

IMO address completion is one of the main features of a mail composer, and I think this feature would help me save a lot of time! :-)