"Start new session" for Windowmaker?

Hello I am trying out using Windowmaker instead of KDE. The only thing that is missing but which I pretty much need is the ability to start a new session. I mean like the "start new session" button on the KMenu. Does anyone know of a script that could be used from Windowmaker? Or even how KDE does it - is there a program or script that gets called when that menu option is chosen? Thanks in advance Steve Dundee, UK