Version: (using KDE 4.1.2) Installed from: Unlisted Binary Package Per default yakuake comes in 90% width. So I change it (via the upside-down triangle button) to 100%, which it accepts. I log out of KDE and back in and once again it's at 90%. As opposed to 163314 in my case even the menu selector ("behind" the upside-down triangle) shows 90%. Nothing is written to ~/.kde4/share/config/yakuakerc nor to ~/.kde4/share/apps/yakuake/ right after setting the size to 100%
I found another thing: if, however, I quit yakuake via the X button, it writes it width to yakuakerc and thus correctly restores it. So the problem seems to be in the way it gets quit (killed?) when I select KickOff->Leave->Shutdown
Unfortunately I'm unable to reproduce this problem on my end. KDE applications usually write out their config when they are quit (either manually, or asked to do so by the KDE session manager on logout), but as there seem to be intermittent problems with Yakuake getting killed by KDE logout instead of being quit properly, I may have to look into changing that. *** This bug has been marked as a duplicate of bug 168402 ***