User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:188.8.131.52) Gecko/2008070206 Firefox/3.0.1
I just compiled and installed the latest revision (27356) of xfwm4.
It doesn't work with kde and wine apps.
When trying to open such an app. xfwm4 stops working.
This version of xfwm4 only seems to work with xfce and gnome apps.
Fixed in revision 27357.