Changing window-titlebar-button arrangement causes KDE to freeze

[mlx]

1) Maverick
2) 4.5.1-0ubuntu1
3) It should be possible to change the arrangement of these buttons on-the-fly
4) after changing the arrangement in the dialog (System Settings > Workspace appearance > Window Decorations > Configure buttons) and clicking "Apply" in the main window, KDE freezes. The pointer is moving but the windows are responding to neither mouse clicks nor keyboard presses. I need to switch to another vtyand 'sudo restart kdm'. I'm using the Plastik decoration scheme

ProblemType: Bug
DistroRelease: Ubuntu 10.10
Package: kde-plasma-desktop (not installed)
ProcVersionSignature: Ubuntu 2.6.35-19.28-generic 2.6.35.3
Uname: Linux 2.6.35-19-generic x86_64
Architecture: amd64
Date: Tue Sep 7 19:23:21 2010
InstallationMedia: Kubuntu 10.10 "Maverick Meerkat" - Alpha amd64 (20100907)
ProcEnviron:
 LANGUAGE=
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: meta-kde