Version: KMail-1.12.4 (using KDE 4.3.4) Compiler: gcc-4.4.2 OS: Linux Installed from: Gentoo Packages The folders in the left part of KMail should enlarge in the same way Dolphin's places do when you drag the vertical bar. See here for example how ugly and empty it looks. http://img204.imageshack.us/img204/3287/kmail.png
Also true for the icon view, it only shows three items in a row no matter how wide or narrow you drag the handle.
can not reproduce in 4.9